Marco Bertamini criticized the Swami et al. study for using a picture of the same person with digitally altered leg lengths which he felt would make the modified image appear unrealistic. [ 78 ]  Bertamini also criticized the Swami study for only changing the leg length while keeping the arm length constant. [ 78 ]  After accounting for these concerns in his own study, Bertamini, using stick figures, also found a preference for women with proportionately longer legs than men. [ 78 ]  When Bertamini investigated the issue of possible  sexual dimorphism  of leg length, he found two sources that indicated that men usually have slightly proportionately longer legs than women or that differences in leg length proportion may not exist between men and women. [ 79 ]  Following this review of existing literature on the subject, he conducted his own calculations using data from 1774 men and 2208 women. Using this data, he similarly found that men usually have slightly proportionately longer legs than women or that differences in leg length proportion may not exist between men and women. These findings made him rule out the possibility that a preference for women with proportionately longer legs than men is due proportionately longer legs being a  secondary sex characteristic  of women. [ 79 ]


A 2006 study of 25,594 heterosexual men found that "men who perceived themselves as having a  large penis  were more satisfied with their own appearance". [ 80 ]


A 2014 study criticized previous studies based on the fact that they relied on images and used terms such as "small", "medium", and "large" when asking for female preference. The new study used 3D models of penises from sizes of 4 inches (10 cm) long and 2.5 inches (6.4 cm) in circumference to 8.5 inches (22 cm) long and 7 inches (18 cm) in circumference and let the women "view and handle" them. It was found that women overestimated the actual size of the penises they experimented with when asked in a follow-up survey. The study concluded that "women on average preferred the 6.5-inch (17 cm) penis in length both for long-term and for one-time partners. Penises with larger girth were preferred for one-time partners." [ 81 ]


Evidence from various cultures suggests that  heterosexual  men tend to find the sight of women's genitalia to be  sexually arousing . [ 82 ]


Manual labourers who spent extended periods of time outside developed a darker  skin tone  due to exposure to the sun. As a consequence, an association between dark skin and the  lower classes  developed. Light skin became an aesthetic ideal because it symbolized wealth. "Over time society attached various meanings to these coloured differences. Including assumptions about a person's race, socioeconomic class, intelligence, and physical attractiveness." [ 84 ]


Some research has suggested that redder and yellower skin tones, [ 85 ]  reflecting higher levels of oxygenated blood, [ 86 ]  carotenoid and to a lesser extent melanin pigment, and net dietary intakes of fruit and vegetables, [ 87 ]  appear healthier, and therefore more attractive. [ 88 ]  However, there is little direct evidence that skin colour is actually related to health or immune system strength. [ 89 ]


A historical preference for lighter-skinned women has been documented across many cultures. [ 90 ] [ 91 ]  However, the accuracy of this research has been questioned by other authors. [ 92 ]  Experimental studies show that white Western men are more attracted to tanned women, rather than pale women, and that women themselves believe that they are more attractive with tan skin. [ 93 ] [ 94 ] [ 95 ]  A 2010 study found a preference for lighter-skinned (but not lightest) women in New Zealand and California. [ 96 ]  However, other research has found that African-American males and females consider medium complexion as more attractive than lighter or darker skin, while white and Hispanic women seek to  tan  their skin in order to increase their attractiveness to the opposite sex. [ 97 ]  There is a direct correlation between being tan and self-perceived attractiveness, especially among young women. [ 98 ]


According to research from  China , since the 2010s, tan skin has emerged as the new beauty ideal for women in China, and Chinese women themselves believe their tan skin is more attractive and healthier than pale skin. [ 99 ]  Similar findings from  Japan  have found that the ideal female skin colour is tan, with no spots or roughness. There is a widepread perception in Japan that White women's skin is less beautiful than Japanese women's, as White women are stereotyped as being too pale and roughly textured. [ 100 ]


The relationship between attractiveness and skin colour may also intersect with ethnicity and prior experience. [ 101 ]  Skin colour preferences may shift over time, as in Western culture, where  tanned skin  used to be associated with the sun-exposed manual labour of the lower-class, but since the mid-20th century it has generally been considered more attractive and healthier than before, with  sun tanning becoming fashionable . [ 102 ] [ 103 ] [ 104 ] [ 105 ] [ 106 ]  In the African state of  Mali ,  skin bleaching  is common as it is thought to improve one's social standing and attractiveness to the opposite sex, although there has also been vocal opposition to this notion from pop culture icons. [ 107 ]


Skin radiance or glowing skin may influence perception of beauty and physical attractiveness. [ 108 ] [ 109 ]


Hands have been found to be physically attractive. [ 110 ]  The type of hands that are physically attractive are those with longer index and ring fingers. [ 111 ]  Men have a smaller index-to-ring-finger ratio than women. The gender differences in the ratio between the index and ring fingers are said to be influenced by exposure to  testosterone  within the womb. [ 112 ]  In a study where participants were shown computer-based images of hands, male participants found  feminine  hands with a smaller index finger less attractive. Whereas females found  masculine  hands with a longer ring finger more attractive. The study suggests that finger length has an effect on physical attraction because it gives indication of the desirable sex-hormone dependent traits which one may possess. [ 111 ]  Another study found that averageness, healthiness of the skin, how fat the hands appear to be, and the grooming of the hands, all affect the attractiveness of hands. [ 113 ]  What is meant by averageness is the degree to which the hands look like an average of the hands in the population. Average-looking hands give an indication of an individual's health (because there are no abnormalities).


The healthier-looking the skin on the hands, the more attractive they appear. Reasons given for this say skin health may reflect an individual's overall health. Healthy skin can show that someone is free from illness because some illnesses have a bad effect on the look of skin. These features are found attractive because they show that the person has good  genes  and is therefore a suitable mate to reproduce with. Skin health may also give an indication of socioeconomic status, as rough hands may indicate a low-paying, laborious job. Low socioeconomic status might show that someone does not have resources to provide for the offspring, and is therefore less attractive. The more fat the hands appear, the less attractive they are. This is because of the  co-morbidity  associated with obesity. If someone is overweight, they may have another disease, which means they may not be able to produce healthy offspring. The attractiveness of the hands also gives an indication of other features of the individual; people with more attractive hands have been found to be taller and slimmer. [ 110 ]  In most of these hand attractiveness studies, only white, European hands were used, and the participants were 18–26 years old. So, the attractiveness of non-white hands and of different age groups was not tested. Also, the people who rated the hand attractiveness were white Europeans, so their ratings may not represent how individuals of other skin colours and cultures would rate the hands.


Females' sexual attraction towards males may be determined by the  height  of the man. [ 114 ]  For example, the dating site eHarmony only matches women with men taller than themselves, because of complaints from women matched with shorter men. [ 65 ]


Other studies have shown that heterosexual women often prefer men taller than they are, rather than a man with above average height. While women usually desire men to be at least the same height as themselves or taller, several other factors also determine male attractiveness, and the "taller male" norm is not universal. [ 115 ]  For example, taller women are more likely to relax the "taller male" norm than shorter women. [ 116 ]  Furthermore, professor Adam Eyre-Walker, from the  University of Sussex , has stated that there is, as yet, no evidence that these preferences are evolutionary preferences, as opposed to merely cultural preferences. [ 117 ]  Still, the cultural perceived attractiveness preferences for taller men are powerful and confirmed by multiple studies. One study of speed-daters by Stulp found that "women were most likely to choose [men] 25 cm taller than themselves, whereas men were most likely to choose women only 7 cm shorter than themselves". [ 118 ]


Additionally, women seem more receptive to an erect posture than men, though both prefer it as an element within  beauty . [ 119 ]  According to one study (Yee N., 2002), gay men who identify as "only  tops " tend to prefer shorter men, while gay men who identify as "only  bottoms " tend to prefer taller men. [ 120 ]


In romances in  Middle English  literature, all of the "ideal" male heroes are tall, and the vast majority of the "valiant" male heroes are tall too. [ 121 ]


Most men tend to be taller than their female partners. [ 21 ]  In Western societies, it has been found that most men prefer women shorter than themselves. [ 122 ]  Nevertheless, height is a more important factor for a woman when choosing a man than it is for a man choosing a woman. [ 123 ]  Western men tend to view women taller than themselves as less attractive, [ 122 ]  and many people view heterosexual couples where the woman is taller to be less ideal. [ 122 ]  Women who are 0.7 to 1.7  standard deviations  below the mean female height have been reported to be the most reproductively successful, [ 117 ]  since fewer tall women get married compared to shorter women. [ 122 ]  However, in other ethnic groups, such as the  Hadza people  from  Tanzania , a study has found that height is irrelevant in choosing a mate. [ 115 ]  Another study found the same preference in rural  Gambia . [ 122 ]


In Middle English literature, "tallness" is a characteristic of ideally beautiful women. [ 124 ]  The British Fashion Model Agents Association (BFMA) says that female models should be at least 5 ft 8 in (1.73 m) tall. [ 125 ]


Standing in a  contrapposto  posture (with bodyweight predominantly supported by one leg which is either straight, or very slightly bent, and with the other leg slightly bent) has been found to be more attractive looking than standing in a more plain, upright posture. This was found to be the case for both men and women. This posture may lower a person's observable waist-hip ratio and make their hips look wider and their waists thinner. For women especially, this can accentuate the curvature of their figure on one side of their body and make them seem more attractive. Such poses have been used in historical sculpture to emphasize an ideal of physical beauty. [ 126 ] [ 127 ]  It has also been demonstrated that the contrapposto posture in women elicits more neural activity in brain areas linked to perception and attractiveness assessments than a standing position. [ 128 ]


The way an individual moves can influence attractiveness and indicate health and age. [ 129 ]  A study reflecting the views of 700 individuals and that involved animated representations of people walking, found that the physical attractiveness of women increased by about 50 percent when they walked with a hip sway. Similarly, the perceived attractiveness of males doubled when they moved with a swagger in their shoulders. [ 130 ]


Women, on average, tend to be more attracted to men who have a relatively narrow waist, a V-shaped torso, wide chest and broad shoulders. Women also tend to be more attracted to men who are taller and larger than they are, and display a high degree of  facial symmetry , as well as relatively masculine facial dimorphism. [ 22 ] [ 23 ]  Women, regardless of sexual orientation, tend to be more interested in a partner's physical attractiveness than men. [ 131 ] [ 132 ] [ 133 ]


The degree of differences between male and female anatomical traits is called  sexual dimorphism . Female respondents in the  follicular phase  of their menstrual cycle were significantly more likely to choose a masculine face than those in menses and  luteal phases , [ 134 ]  (or in those taking  hormonal contraception ). [ 22 ] [ 23 ] [ 135 ] [ 136 ]  This distinction supports the  sexy son hypothesis , which posits that it is evolutionarily advantageous for women to select potential fathers who are more genetically attractive, [ 137 ]  rather than the best caregivers. [ 138 ]  However, women's likeliness to exert effort to view male faces does not seem to depend on their masculinity, but to a general increase with women's testosterone levels. [ 139 ]


It is suggested that the masculinity of facial features is a reliable indication of good health, or, alternatively, that masculine-looking males are more likely to achieve high status. [ 140 ]  However, the correlation between attractive facial features and health has been questioned. [ 141 ]  Sociocultural factors, such as self-perceived attractiveness, status in a relationship and degree of gender-conformity, have been reported to play a role in female preferences for male faces. [ 142 ]  Studies have found that women who perceive themselves as physically attractive are more likely to choose men with masculine facial dimorphism, than are women who perceive themselves as physically unattractive. [ 45 ]  In men, facial masculinity significantly correlates with facial symmetry – it has been suggested that both are signals of developmental stability and genetic health. [ 143 ]  One study called into question the importance of facial masculinity in physical attractiveness in men, arguing that when perceived health, which is factored into facial masculinity, is discounted it makes little difference in physical attractiveness. [ 144 ]  In a cross-country study involving 4,794 women in their early twenties, a difference was found in women's  average  "masculinity preference" between countries. [ 145 ] [ 146 ]


A study found that the same genetic factors cause facial masculinity in both males and females such that a male with a more masculine face would likely have a sister with a more masculine face due to the siblings having shared genes. The study also found that, although female faces that were more feminine were judged to be more attractive, there was no association between male facial masculinity and male facial attractiveness for female judges. With these findings, the study reasoned that if a woman were to reproduce with a man with a more masculine face, then her daughters would also inherit a more masculine face, making the daughters less attractive. The study concluded that there must be other factors that advantage the genetics for masculine male faces to offset their reproductive disadvantage in terms of "health", "fertility" and "facial attractiveness" when the same genetics are present in females. The study reasoned that the "selective advantage" for masculine male faces must "have (or had)" been due to some factor that is not directly tied to female perceptions of male facial attractiveness. [ 147 ]


In a study of 447 gay men in China, researchers said that  tops  preferred feminized male faces,  bottoms  preferred masculinized male faces and  versatiles  had no preference for either feminized or masculinized male faces. [ 148 ]


In pre-modern Chinese literature, the ideal man in  caizi jiaren  romances was said to have "rosy lips, sparkling white teeth" and a " jasper -like face" ( Chinese :  唇 紅 齒 白 、 面 若 冠 玉 ). [ 149 ] [ 150 ]


In  Middle English  literature, a beautiful man should have a long, broad and strong face. [ 151 ]


The physique of a slim waist, broad shoulders and muscular chest are often found to be attractive to both females and males. [ 152 ]  Further research has shown that, when choosing a mate, the traits females look for indicate higher social status, such as dominance, resources, and protection. [ 153 ]  An indicator of health in males (a contributing factor to physical attractiveness) is the android fat distribution pattern which is categorized as more fat distributed on the upper body and abdomen, commonly referred to as the "V shape." [ 153 ]  When asked to rate other men, both heterosexual and homosexual men found low waist-to-chest ratios (WCR) to be more attractive on other men, with the  gay men  showing a preference for lower WCR (more V-shaped) than the straight men. [ 154 ]


Other researchers found waist-to-chest ratio the largest determinant of male attractiveness, with body mass index and waist-to-hip ratio not as significant. [ 155 ]


Women focus primarily on the ratio waist to chest or more specifically waist to shoulder. This is analogous to the waist to hip ratio (WHR) that men prefer. Some studies have shown that attractive bodily traits in the eyes of a heterosexual woman would include a tall, athletic physique, with wide shoulders, and a slim waist area. [ 156 ]  Research has additionally shown that college males had a better satisfaction with their body than college females. [ 157 ]  The research also found that when a college female's waist to hip ratio went up, their body image satisfaction decreased. [ 157 ]


Some research has shown that body weight may have a stronger effect than WHR when it comes to perceiving attractiveness of the opposite sex. It was found that waist to hip ratio played a smaller role in body preference than body weight in regards to both sexes. [ 158 ]


Psychologists Viren Swami and Martin J. Tovee compared female preference for male attractiveness cross culturally, between Britain and Malaysia. They found that females placed more importance on WCR (and therefore  body shape ) in urban areas of Britain and Malaysia, while females in rural areas placed more importance on BMI (therefore weight and body size). Both WCR and BMI are indicative of male status and ability to provide for offspring, as noted by evolutionary theory. [ 159 ]


Females have been found to desire males that are normal weight and have the average WHR for a male. Females view these males as attractive and healthy. Males who had the average WHR but were overweight or underweight are not perceived as attractive to females. This suggests that WHR is not a major factor in male attractiveness, but a combination of body weight and a typical male WHR seem to be the most attractive. Research has shown that men who have a higher waist to hip ratio and a higher salary are perceived as more attractive to women. [ 160 ]


A 1982 study found that an abdomen that protrudes was the "least attractive" trait for men. [ 161 ]


In  Middle English  literature, a beautiful man should have a flat abdomen. [ 162 ]


Men's bodies portrayed in magazines marketed to men are more muscular than the men's bodies portrayed in magazines marketed to women. From this, some have concluded that men perceive a more muscular male body to be ideal, as distinct from a woman's ideal male, which is less muscular than what men perceive to be ideal. [ 163 ]  This is due to the within-gender prestige granted by increased muscularity and within-gender competition for increased muscularity. [ 163 ]  Men perceive the attractiveness of their own musculature by how closely their bodies resemble the "muscle man." [ 164 ]  This "muscle man" ideal is characterized by large muscular arms, especially biceps, a large muscular chest that tapers to their waist and broad shoulders. [ 164 ]  Among Australian university students, the male body composition found to be most attractive (12.16 kg fat, 63.27 kg muscle) was in line with the composition that was perceived as healthiest, and was well within the healthy range. [ 165 ]


In a study of stated profile preferences on Match.com, a greater percentage of gay men than lesbians selected their ideal  partner's  body type as "Athletic and Toned" as opposed to the other two options of "Average" or "Overweight". [ 166 ]


In pre-modern Chinese literature, such as in  Romance of the Western Chamber , a type of masculinity called "scholar masculinity" is depicted wherein the "ideal male lover" is "weak, vulnerable, feminine, and  pedantic ". [ 149 ]


In  Middle English  literature, a beautiful man typically has thick, broad shoulders, a square and muscular chest, a muscular back, strong sides that taper to a small waist, large hands and arms and legs with huge muscles. [ 167 ]


Studies based in the United States, New Zealand, and China have shown that women rate men with no trunk ( chest  and  abdominal ) hair as most attractive, and that attractiveness ratings decline as hairiness increases. [ 168 ] [ 169 ]  Another study, however, found that moderate amounts of trunk hair on men was most attractive, to the sample of British and Sri Lankan women. [ 170 ]  Further, a degree of hirsuteness (hairiness) and a waist-to-shoulder ratio of 0.6 is often preferred when combined with a muscular physique. [ 170 ]


In a study using Finnish women, women with hairy fathers were more likely to prefer hairy men, suggesting that preference for hairy men is the result of either genetics or imprinting. [ 171 ]  Among gay men, another study reported gay males who identify as "only  tops " prefer less hairy men, while gay males who identify as "only  bottoms " prefer more hairy men. [ 120 ]


One study shows that men with facial hair covering the cheeks, upper lip, and lower jaw were perceived as more physically attractive than men with patchy facial hair. [ 172 ]  In this study, men's facial hair was split into four categories, each differing in the thickness and coverage: very light, light, medium, and heavy. Light facial hair was rated as the most attractive, followed by medium, heavy, and the least attractive was 'very light'. This study suggests that some facial hair is better than none because it shows  masculine  development, as beard growth requires the conversion of testosterone. An earlier study found that women from Western and Oceanic cultures are more attracted to clean-shaven faces than beards. However, they also rated full-bearded men as having higher status than clean-shaven men. [ 173 ]


More angular male jawlines tend to be selected as ideal in Western countries, while the ideal female jawline is rounder and softer. [ 174 ] [ 175 ] [ 176 ]


Most research shows that attractive  bigonial width  and Ramus measurements have similarities, but the jutting square chin is a prominently European-heritage trait –  which means it should not be held as a universal indicator of attractiveness. [ 177 ] [ 178 ]  Men with low  submental  fat were viewed to have "better jawlines" and a more "youthful look". [ 179 ]


Research indicates that heterosexual men tend to be attracted to young [ 64 ]  and beautiful women [ 180 ]  with bodily symmetry. [ 181 ]  Rather than decreasing it, modernity has only increased the emphasis men place on women's looks. [ 182 ]   Evolutionary psychologists  attribute such attraction to an evaluation of the  fertility  potential in a prospective mate. [ 64 ]


Research has attempted to determine which facial features communicate attractiveness.  Facial symmetry  has been shown to be considered attractive in women, [ 186 ] [ 187 ]  and men have been found to prefer full lips, [ 188 ]  high forehead, broad face, small chin, small nose, short and narrow jaw, high cheekbones, [ 39 ] [ 189 ]  clear and smooth skin, and wide-set eyes. [ 64 ]  The shape of the face in terms of "how everything hangs together" is an important determinant of beauty. [ 190 ]  Women with thick, dark  limbal rings  in their eyes have also been found to be more attractive. The explanation given is that because the ring tends to fade with age and medical problems, a prominent limbal ring gives an honest indicator of youth. [ 191 ]


In Persian literature, beautiful women are said to have noses like  hazelnuts . [ 192 ]  In Arabian society in the Middle Ages, a component of the female beauty ideal was for women to have straight and fine noses. [ 193 ] In Jewish  Rabbinic literature , the rabbis considered a delicate nose to be the ideal type of nose for women. [ 194 ]  In Japan, during the  Edo period , a component of the female beauty ideal was for women to have tall noses which were straight and not "too tall". [ 195 ]


In a cross-cultural study, more  neotenized  (i.e., youthful looking) female faces were found to be most attractive to men while less neotenized female faces were found to be less attractive to men, regardless of the females' actual age. [ 196 ]  In a study of Italian women who have won beauty competitions, it was found that their faces had more "babyish" ( pedomorphic ) traits than those of the "normal" women used as a reference. [ 197 ]


In a cross-cultural study, Marcinkowska et al. said that 18-to-45-year-old heterosexual men in all 28 countries surveyed preferred photographs of 18-to-24-year-old white women whose faces were feminized using facial image editing software over faces of 18-to-24-year-old white women that were masculinized using that software, but there were differences in preferences for femininity across countries. The higher the National Health Index (based on eight national health statistics taken from the World Health Organization Statistical Information Service using data from 2002 to 2006) of a country, the more were the feminized faces preferred over the masculinized faces. Among the countries surveyed, Japan had the highest femininity preference and Nepal had the lowest femininity preference. [ 198 ]


Michael R. Cunningham of the Department of Psychology at the  University of Louisville  found, using a panel of  East Asian ,  Hispanic  and  White  judges, that the female faces tended to be judged as more attractive if they had a mixture of youthful and sexually mature features. [ 199 ]  Using a panel of  African Americans  and Whites as judges, Cunningham found more neotenous faces were perceived as having both higher "femininity" and "sociability". [ 90 ]  The authors found no evidence of ethnocentric bias in the Asian or White samples, as Asians and Whites did not differ significantly in preference for neonate cues, and positive ratings of White women did not increase with exposure to  Western media . [ 200 ]


Rather than finding evidence for purely "neonate" faces being most appealing, Cunningham found faces with "sexually-mature" features at the "periphery" of the face combined with "neonate" features in the "centre of the face" most appealing in women. [ 90 ]  Upon analyzing the results of his study, Cunningham concluded that preference for "neonate features may display the least cross-cultural variability" in terms of "attractiveness ratings" [ 90 ]  and, in another study, Cunningham concluded that there exists a large agreement on the characteristics of an attractive face. [ 201 ]


In computer face averaging tests, women with  averaged  faces have been shown to be considered more attractive. [ 31 ] [ 202 ]  This is possibly due to average features being more familiar and, therefore, more comfortable. [ 186 ]


According to Chinese scholar Liu Jieyu (2008), there is more pressure on women than men to be physically attractive. Whereas there are various criteria that women might be expected to meet, a man might only need to be tall to be considered attractive. [ 203 ]


On average, symmetrical features are one ideal, while unusual, stand-out features are another. [ 204 ]  A study performed by the University of Toronto found that the most attractive facial dimensions were those found in the average female face. However, that particular University of Toronto study looked only at white women. [ 205 ]


A 2011 study, by Wilkins, Chan and Kaiser found correlations between perceived femininity and attractiveness; that is, women's faces which were seen as more feminine were judged by both men and women to be more attractive. [ 206 ]  The study also found that  East Asian  women's faces were more "prototypically" feminine than White women's, a finding that was replicated by several follow-up studies which found that this explains the higher attractiveness ratings of East Asian women compared to White women. [ 207 ] [ 208 ]


A component of the female beauty ideal in  Persian literature  is for women to have faces like a full moon. [ 192 ] [ 209 ] [ 210 ]


Similarly, in Arabian society in the Middle Ages, a component of the female beauty ideal was for women to have round faces which were like a "full moon". [ 193 ]


In Japan, during the  Edo period , a component of the female beauty ideal was for women to have oval-shaped faces. [ 195 ]


In Jewish  Rabbinic literature , the rabbis considered full lips to be the ideal type of lips for women. [ 194 ]


Historically, in Chinese and Japanese literature, the feminine ideal was said to include small lips. [ 211 ]  Women would paint their lips thinner and narrower to align with this ideal. [ 212 ] [ 213 ]


A study that used Chinese, Malay and Indian judges said that Chinese women and Chinese men with retrusive mandibles (where the mouth is flat and in-line with the rest of the face) were judged to be the most attractive and Chinese men and Chinese women with a protruding mandible (where the jaw projects outward) were judged to be the least attractive. [ 214 ]


Classical Persian literature, paintings and miniatures portrayed traits such as long black curly hair, a small mouth, long arched eyebrows, large almond-shaped eyes, a small nose, and beauty spots as being beautiful for women. [ 215 ]


A study that investigated whether or not an eyelid crease makes Chinese-descent women more attractive using  photo-manipulated  photographs of young Chinese-descent women's eyes found that the "medium upper  eyelid  crease" was considered most attractive by all three groups of both sexes: white people,  Chinese  and  Taiwanese  nationals together as a group, and  Taiwanese  and  Chinese Americans  together as a group. Similarly, all three groups of both genders found the absence of an eye crease to be least attractive on Chinese women. [ 216 ]


In the late sixteenth century, Japanese people considered  epicanthic folds  to be beautiful. [ 217 ]


A study that used Russian, American, Brazilian,  Aché , and  Hiwi  raters, found that the only strong distinguisher between men and women's faces was wider eyes relative to facial height for women, and this trait consistently predicted attractiveness ratings for women. [ 218 ]


In Arabian society in the Middle Ages, a component of the female beauty ideal was for women to have dark black eyes which are large and long and in the shape of almonds. Furthermore, the eyes should be lustrous, and they should have long eyelashes. [ 193 ]


A source written in 1823, said that a component of the Persian female beauty ideal was for women to have large eyes which are black in colour. [ 209 ]  In Persian literature, beautiful women are said to have eyes that are shaped like almonds. [ 192 ]


In Chinese, the phrase "lucent irises, lustrous teeth" ( Chinese :  明   眸   皓   齒 ) is used to describe a beautiful woman with "clear eyes" and "well-aligned, white teeth", [ 219 ]  and the phrase "moth-feeler eyebrows" ( Chinese :  蛾眉 ) is used to denote a beautiful woman by describing her eyebrows as being thin and arched like moth  antennae . [ 219 ]  In the Chinese text  The Grotto of the Immortals  ( Chinese :  遊   仙   窟 ) written during the  Tang dynasty  period, narrow eyes were the preferred type of eyes for women, and, in the Chinese text  Jeweled Chamber Secrets  ( Chinese :  玉   房   秘   訣 ) from the  Six Dynasties  period, the ideal woman was described as having small eyes. [ 220 ]


The 1813 Japanese text  Customs, Manners, and Fashions of the Capital  ( Japanese :  都   風   俗   化   粧   伝 ) indicates that large eyes were not considered attractive in women. [ 221 ]


Research has shown that most heterosexual men enjoy the sight of female  breasts , with a preference for firm breasts [ 222 ] [ 223 ]  A study of British undergraduates found men preferred small breasts on women. [ 224 ]  Smaller breasts were widely associated with youthfulness. [ 129 ]  Cross-culturally, another study found "high variability" regarding the ideal breast size. [ 224 ]


The pigmentation of nipples and breasts appears to be the most important quality of breast attractiveness. Men rated women with dark nipples and dark areola as significantly more attractive than those with light-coloured nipples or areola. [ 225 ]  Breasts of medium cup size were found to be the most attractive, however it was noted that men focused primarily on the colouration of nipples and areola rather than breast size. [ 225 ]


A study by Groyecka et al., in which they examined Poles and Yali of New Guinea, demonstrated that men's judgements of breast appearance are affected by the occurrence of  breast ptosis  (i.e., sagginess, droopiness). [ 226 ]  Greater breast ptosis (more sagging breasts) is perceived as less attractive and attributed to a woman of older age. These findings are consistent with previous research that link breast attractiveness with female youthfulness. Unlike breast size, breast ptosis seems to be a universal marker of female breast attractiveness.


A study showed that men prefer symmetrical breasts. [ 181 ] [ 227 ]  Breast symmetry may be particularly sensitive to developmental disturbances and the symmetry differences for breasts are large compared to other body parts. Women who have more symmetrical breasts tend to have more children. [ 228 ]


Historical literature often includes specific features of individuals or a gender that are considered desirable. These have often become a matter of convention, and should be interpreted with caution. In Arabian society in the Middle Ages, a component of the female beauty ideal was for women to have small breasts. [ 193 ]  In Persian literature, beautiful women are said to have breasts like  pomegranates  or lemons. [ 192 ]  In the Chinese text  Jeweled Chamber Secrets  ( Chinese :  玉   房   秘   訣 ) from the  Six Dynasties  period, the ideal woman was described as having firm breasts. [ 220 ]  In  Sanskrit literature , beautiful women are often said to have breasts so large that they cause the women to bend a little bit from their weight. [ 229 ]  In  Middle English  literature, beautiful women should have small breasts that are round like an apple or a pear. [ 230 ]


Biological anthropologist  Helen E. Fisher  of the centre for Human Evolution Studies in the Department of Anthropology of  Rutgers University  said that, "perhaps, the fleshy, rounded  buttocks ... attracted males during  rear-entry intercourse ." [ 231 ]  In a recent study, using 3D models and eye-tracking technology Fisher's claim was tested and was shown that the slight thrusting out of a woman's back influence how attractive others perceive her to be and captures the gaze of both men and women. [ 232 ] [ 233 ]  Bobbi S. Low et al. of the School of Natural Resources and Environment at the  University of Michigan , said the female "buttocks evolved in the context of females competing for the attention and parental commitment of powerful resource-controlling males" as an "honest display of fat reserves" that could not be confused with another type of tissue, [ 234 ]  although  T. M. Caro , professor in the centre for Population Biology and the Department of Wildlife, Fish, and Conservation Biology, at  University of California, Davis , rejected that as being a necessary conclusion, stating that female fatty deposits on the hips improve "individual  fitness  of the female", regardless of  sexual selection . [ 234 ]


In a 1995 study, black men were more likely than white men to use the words "big" or "large" to describe their conception of an attractive woman's posterior. [ 235 ]  In a 2009 experiment to research what South African, British white and British African men considered to be the most attractive size of posterior and breasts for white and black women. This image shown here only shows the two extreme variations of size on black female figures used in the experiment. The left-hand figure received the highest average attractiveness rating from South African men while a figure with an intermediate size received the highest ratings from both white and black British men. The right-hand figure  did not receive the highest average attractiveness rating from any group. [ 236 ]


Body Mass Index  (BMI) is an important determinant to the perception of beauty. [ 237 ]  Even though the Western ideal is for a thin woman, some cultures prefer plumper women, [ 90 ] [ 238 ]  which has been argued to support that attraction for a particular BMI merely is a cultural artifact. [ 238 ]  The attraction for a proportionate body also influences an appeal for  erect posture . [ 239 ]  One cross-cultural survey comparing body-mass preferences among 300 of the most thoroughly studied cultures in the world showed that 81% of cultures preferred a female body size that in English would be described as "plump". [ 240 ]


Availability of food influences which female body size is attractive which may have evolutionary reasons. Societies with food scarcities prefer larger female body size than societies that have plenty of food. In Western society, males who are hungry prefer a larger female body size than they do when not hungry. [ 241 ]


BMI has been criticised for conflating fat and muscle, and more recent studies have concentrated on body composition. Among Australian university students, the most attractive body composition for women (10.31 kg fat, 42.45 kg muscle) was found to be lower in fat than both the most healthy appearing composition, and below the healthy range. [ 165 ]


In the United States, women overestimate men's preferences for thinness in a mate. In one study, American women were asked to choose what their ideal build was and what they thought the build most attractive to men was. Women chose slimmer than average figures for both choices. When American men were independently asked to choose the female build most attractive to them, the men chose figures of average build. This indicates that women may be misled as to how thin men prefer women to be. [ 238 ]  Some researchers believe women themselves may play a role in enforcing the thinness ideal, however they assert that this does not mean that the ideal does not ultimately trace its origins to patriarchical norms (the " male gaze "). [ 242 ]  Popenoe writes that societies with abundant food sources often value thin women, while those with food scarcity value women with fat bodies. In the West, women with thin bodies became the ideal in the 19th century, as the fat body became associated with criminality and backwardness. [ 243 ]  Some implicated the fashion industry for the promulgation of the notion of thinness as attractive. [ 244 ] [ 245 ]


East Asians have historically preferred women whose bodies had small features. For example, during the  Spring and Autumn period  of Chinese history, women in Chinese harems wanted to have a thin body in order to be attractive for the Chinese emperor. Later, during the  Tang dynasty , a less thin body type was seen as most attractive for Chinese women. [ 246 ]  In Arabian society in the Middle Ages, a component of the female beauty ideal was for women to be slender like a "cane" or a "twig". [ 193 ]  In the Chinese text  Jeweled Chamber Secrets  ( Chinese :  玉   房   秘   訣 ) from the  Six Dynasties  period, the ideal woman was described as not being "large-boned". [ 220 ]


In the  Victorian era , women who adhered to Victorian ideals were expected to limit their food consumption to attain the ideal slim figure. [ 247 ]  In  Middle English  literature, "slender" women are considered beautiful. [ 248 ]


According to research on females, women consider a full body with good distribution to be highly important to be considered attractive by men. [ 249 ]


A WHR of 0.7 for women has been shown to correlate strongly with general  health  and  fertility . Women within the 0.7 range have optimal levels of  estrogen  and are less susceptible to major diseases such as  diabetes , heart disease, and ovarian cancers. [ 250 ]  Women with high WHR (0.80 or higher) have significantly lower pregnancy rates than women with lower WHRs (0.70–0.79), independent of their BMIs. [ 251 ] [ 252 ]  Female waist-to-hip ratio (WHR) has been proposed by evolutionary psychologists to be an important component of human male  mate choice , because this trait is thought to provide a reliable cue to a woman's reproductive value. [ 253 ]


Both men and women judge women with smaller waist-to-hip ratios more attractive. [ 254 ]  Ethnic groups vary with regard to their ideal waist-to-hip ratio for women, [ 255 ]  ranging from 0.6 in China, [ 256 ]  to 0.8 or 0.9 in parts of South America and Africa, [ 257 ] [ 258 ] [ 259 ]  and divergent preferences based on ethnicity, rather than nationality, have also been noted. [ 260 ] [ 261 ]  A study found the  Machiguenga people , an isolated indigenous South American ethnic group, prefer women with high WHR (0.9). [ 262 ]  The preference for heavier women, has been interpreted to belong to societies where there is no risk of obesity. [ 263 ]


In Chinese, the phrase "willow waist" ( Chinese :  柳   腰 ) is used to denote a beautiful woman by describing her waist as being slender like a willow branch. [ 219 ]


In the  Victorian era , a small waist was considered the main trait of a beautiful woman. [ 247 ]  The term " wasp waist " describes an extreme fashion silhouette, produced by a style of corset and girdle.


According to some studies, most men prefer women with small feet, [ 264 ] [ 265 ]  such as in ancient China where  foot binding  was practiced. [ 266 ]


In Jewish  Rabbinic literature , the rabbis considered small feet to be the ideal type of feet for women. [ 194 ]


Men have been found to prefer  long-haired  women. [ 64 ] [ 267 ]   [ 268 ]  An  evolutionary psychology  explanation for this is that malnutrition and deficiencies in minerals and vitamins causes loss of hair or hair changes. Hair therefore indicates health and nutrition during the last 2–3 years. Lustrous hair is also often a cross-cultural preference. [ 129 ]


A component of the female beauty ideal in  Persian literature  is for women to have black hair, [ 269 ]  which was also preferred in Arabian society in the Middle Ages. [ 193 ]  In Middle English literature, curly hair is a necessary component of a beautiful woman. [ 270 ]


There are some subtle changes in women's perceived attractiveness across the  menstrual cycle . During their most  fertile phase , we can observe some changes in women's behaviour and physiology. A study conducted by G. Miller (2007) examined the amount of tip earnings by lap dancers across the menstrual cycle. He found that dancers received nearly US$15 more when they were near  ovulation  than during the rest of the month. This suggests that women either are more attractive during ovulation phase, or they experience a significant change in their behaviour. [ 271 ]  Some other studies have found that there are subtle differences in women's faces when in their  fertile  phase. Bobst and Lobmaier (2012) created 20 prototyped photographs, some of a female during ovulation and some during the  luteal phase . Men were asked to choose the more attractive, the more caring and the more flirtatious faces. They found a significant preference for the  follicular phase  (ovulation). This suggests that subtle shape differences in faces occurring during the female's  ovulation  phase are sufficient to attract men more. [ 272 ]  This idea is supported by another study, where a similar experiment was done. Men and women had to judge photographs of women's faces taken during their  fertile phase . They were all rated more attractive than during  non-fertile phase . There are some subtle visible cues to ovulation in women's faces, and they are perceived as more attractive, leading to the idea that it could be an adaptive mechanism to raise a female's mate value at that specific time (when probability of conception is at its highest). [ 271 ]


Women's attractiveness, as perceived by men and women, slightly differs across her menstrual cycle, being at peak when she is in her ovulation phase. Jones et al. (2008), focused on women's preferences for  masculinity , apparent health and self-resemblance and found that it varies across the cycle. They explained that the function of the effects of menstrual cycle phase on preferences for apparent health and self-resemblance in faces is to increase the likelihood of  pregnancy . [ 273 ]


Similarly, females prefer the scent of  symmetrically faced  men and men with masculine faces during fertile phases as well as stereotypical male displays such as social presence, and direct  intrasexual  competitiveness. [ 274 ]


During the  follicular  phase (fertile), females prefer more masculine traits ( testosterone  dependent traits such as face shape) than when in non-fertile phase. Those findings have been found in the voice, showing that females' preferences for more masculine voices over feminine voices increase the fertile phase of the menstrual cycle. [ 275 ]


But not only females' preferences vary across cycle, their behaviours as well. Effectively, men respond differently to females when they are on ovulatory cycle, [ 271 ]  because females act differently. Women in the ovulatory phase are flirtier with males showing  genetic  fitness markers than in low fertile phase. [ 276 ]  It has been shown in some studies that women high in  estrogen  are generally perceived to be more attractive than women with low levels of estrogen, based on women not wearing make-up. High estrogen level women may also be viewed as healthier or to have a more  feminine  face. [ 277 ]


Similarly, a study investigated the capacity of women to select high quality males based on their facial attractiveness. They found that facial attractiveness correlated with  semen  quality (good, normal, or bad depending on  sperm  morphology and motility). The more attractive a man's face is, linked to his sperm being of better quality. [ 278 ]


Sexual ornaments  are seen in many organisms; in humans, females have sexual ornamentation in the form of breasts and buttocks. The physical attraction to sexual ornaments is associated with  gynoid fat , as opposed to  android fat , which is considered unattractive. [ 279 ]  In human females, proximate causes of the development of sexual ornaments are associated with the predominance of estrogen in puberty. The activation of  estrogen receptors  around the female skeletal tissue causes gynoid fat to be deposited in the breasts, buttocks, hips and thighs, producing an overall typical female body shape. [ 280 ]  Specifically, female breasts are considered more attractive when symmetrical, rather than asymmetrical, [ 281 ]  as this is thought to reflect good  developmental stability . [ 282 ]


Sexual ornaments are considered attractive features as they are thought to indicate high mate value, fertility, [ 283 ]  and the ability to provide good care to offspring. They are  sexually selected  traits present for the purpose of  honest signalling  and capturing the visual attention of the opposite sex, most commonly associated with females capturing the visual attention of males. It has been proposed that these ornaments have evolved in order to advertise personal quality and  reproductive value . [ 284 ]  Honest signalling with sexual ornaments is associated with ultimate causation of these evolved traits. The evolution of these ornaments is also associated with female-female competition in order to gain material benefits provided by resourceful and high status males. [ 285 ]  In humans, once these sexual ornaments develop, they are permanent. It is thought that this is associated with the long-term pair bonding humans engage in; human females engage in extended sexual activity outside of their fertile period. [ 286 ]  This relates to another ultimate cause of sexual ornaments with function in obtaining non-genetic material benefits from males. In other animal species, even other primate species, these advertisements of reproductive value are not permanent. Usually, it is the point at which the female is at her most fertile, she displays  sexual swellings . [ 287 ]


Adolescence  is the period of time whereby humans experience  puberty , and experience anatomical changes to their bodies through the increase of sex hormones released in the body. Adolescent exaggeration is the period of time at which sexual ornaments are maximised, and peak gynoid fat content is reached. [ 285 ]  In human females, the mean age for this is approximately 16 years. Female breasts develop at this stage not only to prepare for reproduction, but also due to competition with other females in displaying their reproductive value and quality to males. [ 285 ]


In the  social psychology  perspective, interpersonal attraction is when someone experiences a positive attitude or evaluation regarding a particular person having potential of being a significant other. This includes "three components conventionally ascribed to  attitudes: behavioural (tendency to approach the person), cognitive (positive beliefs about the person), and affective (positive feelings for the person)." [ 288 ]  With these three components,  psychology  has created five elements of interpersonal attraction. These include proximity, similarity, physical attractiveness, reciprocity, and responsiveness. [ 289 ]


Most studies of the brain activations associated with the perception of attractiveness show photographs of faces to their participants and let them or a comparable group of people rate the attractiveness of these faces. Such studies consistently find that activity in certain parts of the  orbitofrontal cortex  increases with increasing attractiveness of faces. [ 290 ] [ 291 ] [ 285 ] [ 292 ] [ 293 ]  This neural response has been interpreted as a reaction on the rewarding nature of attractiveness, as similar increases in activation in the medial orbitofrontal cortex can be seen in response to smiling faces [ 294 ]  and to statements of morally good actions. [ 285 ] [ 293 ]  While most of these studies have not assessed participants of both genders or homosexual individuals, evidence from one study including male and female hetero- and homosexual individuals indicate that some of the aforementioned increases in brain activity are restricted to images of faces of the gender which participants feel sexually attracted to. [ 295 ]


With regard to brain activation related to the perception of attractive bodies, one study with heterosexual participants suggests that activity in the nucleus accumbens and the anterior cingulate cortex increases with increasing attractiveness. The same study finds that for faces and bodies alike, the medial part of the orbitofrontal cortex responds with greater activity to both very attractive and very unattractive pictures. [ 296 ]  Recent research has found that the perception of women with lower Waist-to-Hip Ratios and larger breasts triggers distinct patterns of temporal and spatial brain activation, differing from those associated with larger WHRs and smaller breasts. [ 297 ]  Specifically, attractive WHRs and breast sizes influenced brain activity related to visual processing differently than less attractive WHRs and breast sizes, impacting both early and late stages of temporal processing in men and women. [ 297 ]  Moreover, research on upper body size shows that posterior brain regions are involved in perceiving body forms of differing attractiveness due to variations male upper body size, while frontal brain regions are engaged when these perceptions are explicitly rated. [ 298 ]  Such brain activities are unique to processing male, but not female, body sizes.


For both men and women, there appear to be universal criteria of attractiveness both within and across cultures and ethnic groups. [ 19 ] [ 299 ]  When considering long-term relationships, some studies have found that men place a higher emphasis on physical attractiveness in a partner than women do. [ 300 ] [ 301 ] [ 302 ] [ 303 ] [ 304 ]  On the other hand, some studies have found few differences between men and women in terms of the weight they place on physical characteristics when they are choosing partners for short-term relationships, [ 305 ] [ 306 ] [ 307 ] [ 308 ]  in particular with regard to their implicit, as opposed to explicitly articulated, preferences. [ 309 ]  Other recent studies continue to find sex differences for long-term relationships. [ 310 ] [ 311 ] [ 312 ] [ 307 ]  While still valuing physical attractiveness, women tend to prioritize a man's status over his physical attractiveness, while men prioritize physical attractiveness over status. [ 313 ]  There is also one study suggesting that only men, not women, place greater priority on bodily compared to facial attractiveness when looking for a short-term as compared to a long-term partner. [ 314 ]


Some evolutionary psychologists, including David Buss, have argued that this long-term relationship difference may be a consequence of ancestral humans who selected partners based on  secondary sexual characteristics , as well as general indicators of fitness which allowed for greater reproductive success as a result of higher fertility in those partners, [ 315 ]  although a male's ability to provide resources for offspring was likely signaled less by physical features. [ 302 ]  It is argued that the most prominent indicator of fertility in women is youth, [ 316 ] [ 317 ] [ 318 ]  while the traits in a man which enhance reproductive success are proxies for his ability to accrue resources and protect. [ 318 ]


Studies have shown that women pay greater attention to physical traits than they do directly to earning capability or potential to commit, [ 319 ]  including muscularity, fitness and masculinity of features; the latter preference was observed to vary during a woman's period, with women preferring more masculine features during the late-follicular (fertile) phase of the menstrual cycle. [ 275 ] [ 320 ]  Additionally, women process physical attractiveness differently, paying attention to both individual features and the aesthetic effect of the whole face. [ 321 ]


According to Bonnie Adrian, Taiwanese brides place great importance on physical attractiveness for their wedding photographs. These brides go through hours of makeup to transform themselves into socially constructed beauty. Adrian notes that female beauty standards and practices in Taiwan are quite different from those found in the West. Women in Taiwan tend to avoid tanning, while Taiwanese women with tanned skin tones would be considered the ideal in the Western world. [ 322 ]


According to strategic pluralism theory, men may have correspondingly evolved to pursue reproductive strategies that are contingent on their own physical attractiveness. More physically attractive men accrue reproductive benefits from spending more time seeking multiple mating partners and relatively less time investing in offspring. In contrast, the reproductive effort of physically less attractive men, who therefore will not have the same mating opportunities, is better allocated either to investing heavily in accruing resources, or investing in their mates and offspring and spending relatively less time seeking additional mates. [ 323 ]


Research has suggested that people give high attractiveness ratings to same-sex people who  look like them , but only in a nonsexual context. On the other hand, people generally do not find similar-looking people of the opposite sex to be sexually attractive. It is theorized that people may prefer sexual partners who look different from them, which is consistent with a pattern of  inbreeding avoidance . [ 324 ] [ 325 ] [ 326 ]  Although one study found that individuals show a preference for similar-looking mates, after a physiological stress test they preferred dis-similar looking mates. [ 327 ] [ 328 ]


One study found no strong evidence for a same-race preference in heterosexual people, and they note that evidence from two similar studies is conflicting. Some racial groups show a strong preference for partners of a different race or ethnicity, and this preference may be  gendered . [ 329 ] [ 330 ]  One study suggested that attraction to people with different ethnic features may be related to the effects of  heterozygosity , which are thought to be a fitness advantage. [ 331 ]


A 2012 study using British raters found that Asian women's faces were rated as more feminine, and therefore more attractive, than White women's, which could explain the high rate of interracial marriage with Asian women. [ 207 ]  A 2018 facial manipulation experiment conducted in Australia was consistent with these hypotheses, finding both Asian and White participants chose to reduce Asian women's "masculine" facial traits less than White women's, which the authors conclude suggests that Asian faces may be more feminine to begin with. [ 208 ]


In contrast, a 2013 Australian study on facial attractiveness with Asian and White participants found that Asian and White women's faces were not different in attractiveness overall, although a slight own-race bias was observed. However, when rating composite faces (the average of many faces, grouped by race, as opposed to real faces), all participants rated the composite faces more highly and rated White women's composite faces the highest. In a follow-up experiment, the researchers found that there was no difference in Asian and White women's perceived facial femininity. [ 332 ]


A 2008 American study on female facial attractiveness with majority White participants (with a significant proportion of Asian, and few Black, Hispanic, or Middle-Eastern participants) found that White women's faces were rated most attractive. The study showed gradations of computer-generated racial mixes to the participants in increments of one-quarter. The top three rated faces were 100% White, 75% White 25% Black, and 75% White 25% Asian. To the researchers' surprise, Asian women's faces were rated significantly less attractive than White or Black faces in this study. [ 333 ]


A 2012 study using Black and Caucasian subjects found that inter-ethnic and intra-ethnic differences in perceived male facial masculinity have no impact on attractiveness, and that skin colour plays a more important role in attractiveness assessments of male faces within groups, but not between groups as a health signal. [ 334 ]


The  group attractiveness effect  is where a group's overall attractiveness rating is higher than the mean of each individuals' attractiveness rating. This occurs because people selectively attend to the most attractive group members [ 335 ]  and thus they get the most attention. Men selectively attend to attractive people more than women, it has been suggested that this could be because men are less invested in their  offspring , so they are less choosy when it comes to sexual partners, and therefore they are more easily attracted. As a result of selective attention, people end up giving a group rating which is biased as the rating focuses mainly on the attractive members and ignores the less attractive members. So the overall attractiveness rating is skewed towards more attractive. The group attractiveness effect was investigated in a study which got participants to rate the physical attractiveness of a group of females as a whole, individually in a group, and individually on their own. [ 336 ]  Participants were asked to give a rating of 1–7, with 1 being very unattractive and 7 being very attractive. The group attractiveness effect has been replicated with males as the main group and also with a group of both males and females. This effect may not be demonstrated across all cultures because the sample only contained Dutch university students.


Perceptions of physical attractiveness contribute to generalized assumptions based on those attractions. Individuals assume that when someone is beautiful, then they have many other positive attributes that make the attractive person more likeable. [ 18 ]  This is referred to as the  halo effect , also known as the 'beautiful-is-good' effect. [ 18 ]  Across cultures, what is beautiful is assumed to be good; attractive people are assumed to be more extroverted, popular, and happy. This could lead to a  self-fulfilling prophecy , as, from a young age, attractive people receive more attention that helps them develop these characteristics. [ 337 ] [ 338 ]  In one study, beautiful people were found to be generally happier than less beautiful or plain people, perhaps because these outgoing personality traits are linked to happiness, or perhaps because beauty led to increased economic benefits which partially explained the increased happiness. [ 190 ]  In another study testing  first impressions  in 56 female and 17 male participants at  University of British Columbia , personality traits of physically attractive people were identified more positively and more accurately than those who were less physically attractive. It was explained that people pay closer attention to those they find physically beautiful or attractive, and thus perceiving attractive individuals with greater distinctive accuracy. The study believes this accuracy to be subjective to the eye of the beholder. [ 339 ]  Recent results from the Wisconsin  Longitudinal Study  confirmed the positive link between  psychological well-being  and attractiveness (higher facial attractiveness, lower BMI) and also found the complementary negative association with distress/ depression . Even though connections and confounds with other variables could not be excluded, the effects of attractiveness in this study were the same size as the ones for other demographic variables. [ 340 ]


In developed western societies, women tend to be judged for their physical appearance over their other qualities and the pressure to engage in beauty work is much higher for women than men. Beauty work is defined as various beauty "practices individuals perform on themselves or others to elicit certain benefits from a specific social hierarchy." [ 341 ]  Being "beautiful" has individual, social and institutional rewards. [ 341 ]  Although marketers have started to target the "metro-sexual" male and produce hygiene and beauty products geared towards men, the expectations placed on them is less than women. [ 342 ]  The time and money required for a man to achieve the same well-groomed appearance is much lower. Even in areas that men also face pressure to perform beauty work, such as haircuts/styling, the prices discrepancy for products and services are skewed. This phenomenon is called the " pink tax ." [ 343 ] [ 344 ]


However, attractiveness varies by society; in ancient China  foot binding  was practiced by confining young girls' feet in tightly bound shoes to prevent the feet from growing to normal size causing the women to have an attractive "lotus gait". In England, women used to wear corsets that severely constricted their breathing in order to achieve a visual effect of an exaggeratedly low waist-to-hip ratio.


People make judgments of physical attractiveness based on what they see, but also on what they know about the person. Specifically, perceptions of beauty are malleable such that information about the person's personality traits can influence one's assessment of another person's physical beauty. A 2007 study had participants first rate pictures for attractiveness. After doing distracting math problems, participants saw the pictures again, but with information about the person's personality. When participants learned that a person had positive personality characteristics (e.g., smart, funny, kind), that person was seen as more physically attractive. [ 345 ]  Conversely, a person with negative personality characteristics (e.g., materialistic, rude, untrustworthy) was seen as less physically attractive. This was true for both females and males.


Physical attractiveness can have various social effects. For instance, humans tend to self-organize into couples where both parties have loosely similar attractiveness levels as judged by third parties. [ 346 ] [ 347 ] [ 348 ]  A survey conducted by  London Guildhall University  of 11,000 people showed that those who subjectively describe themselves as physically attractive earn more income than others who would describe themselves as less attractive. [ 26 ]  People who described themselves as less attractive earned, on average, 13% less than those who described themselves as more attractive, while the penalty for being overweight was around 5%. According to further research done on the correlation between looks and earnings in men, the punishment for unattractiveness is greater than the benefits of being attractive. However, in women the punishment is found to be equal to the benefits. [ 349 ]  Another study suggests that more physically attractive people are significantly more likely on average to earn considerably higher wages. Differences in income due to attractiveness was much more pronounced for men rather than women, and held true for all ranges of income. [ 350 ]  In the US the earnings disparities along the attractiveness continuum (net of controls) are similar or greater than the black-white disparity. [ 351 ]  A study from 2020 found that social scientists who are judged as being more attractive receive higher public speaking fees than less attractive social scientists, whereas for natural scientists, relative unattractiveness is a comparative advantage in terms of public speaking fees. [ 352 ]


It is important to note that other factors such as self-confidence may explain or influence these findings as they are based on self-reported attractiveness as opposed to any sort of objective criteria; however, as one's self-confidence and  self-esteem  are largely learned from how one is regarded by their peers while maturing, even these considerations would suggest a significant role for physical appearance. One writer speculated that "the distress created in women by the spread of unattainable ideals of female beauty" might possibly be linked to increasing incidence of depression. [ 353 ]


Many have asserted that certain advantages tend to come to those who are perceived as being more attractive, including the ability to get better jobs and promotions; receiving better treatment from authorities and the  legal system ; having more choices in romantic or platonic partners and, therefore, more power in relationships; and marrying into families with more money. [ 30 ] [ 190 ] [ 337 ] [ 338 ] [ 354 ]  Those who are attractive are treated and judged more positively than those who are considered unattractive, even by those who know them. Also, attractive individuals behave more positively than those who are unattractive. [ 355 ]  One study found that teachers tend to expect that children who are attractive are more intelligent, and are more likely to progress further in school. They also consider these students to be more popular. [ 356 ]  Voters choose political candidates who are more attractive over those who are less attractive. [ 357 ]  Men and women use physical attractiveness as a measure of how "good" another person is. [ 358 ]  In 1946, Soloman Asch coined the Implicit Personality Theory, meaning that the presence of one trait tends to imply the existence of other traits. This is also known as the halo effect. Research suggests that those who are physically attractive are thought to have more socially desirable personalities and lead better lives in general. [ 11 ]  This is also known as the "what-is-beautiful-is-good effect" or  physical attractiveness stereotype . Discrimination against or prejudice towards others based on their appearance is sometimes referred to as  lookism  (prejudice or discrimination based on physical appearance and especially physical appearance believed to fall short of societal notions of beauty). [ 359 ]


Some researchers conclude that little difference exists between men and women in terms of  sexual behaviour . [ 301 ] [ 360 ]  Other researchers disagree. [ 361 ]   Symmetrically faced  men and women have a tendency to begin to have  sexual intercourse  at an earlier age, to have more sexual partners, to engage in a wider variety of  sexual activities , and to have more  one-night stands . They are also prone to  infidelity  and are more likely to have  open relationships . [ 46 ]  Additionally, they have the most  reproductive success . Therefore, their physical characteristics are most likely to be inherited by future generations. [ 362 ] [ 363 ] [ 364 ] [ 365 ]


Concern for improving physical attractiveness has led many persons to consider alternatives such as  cosmetic surgery . It has led scientists working with related disciplines such as  computer imaging  and  mathematics  to conduct research to suggest ways to surgically alter the distances between facial features in order to make a face conform more closely to the "agreed-upon standards of attractiveness" of an ideal face by using algorithms to suggest an alternative which still resembles the current face. [ 28 ]  One research study found that cosmetic surgery as a way to "boost earnings" was "not profitable in a monetary sense." [ 190 ]  Some research shows that physical attractiveness has a marginal effect on happiness. [ 366 ]


The golden ratio , also known as the golden proportion, was considered the perfect measurement of harmony, beauty and proportion in  Ancient Greece . Researchers Mohammad Khursheed Alam, Nor Farid Mohd Noor, Rehana Basri, Tan Fo Yew and Tay Hui Wen conducted a study to test if the golden ratio was a contributor to perceptions of facial attractiveness in various ethnic groups. A total of 286 people aged 18 to 25 participated in the survey, including 100  Malay  (50 male, 50 female), 100  Malaysian Chinese  (50 male, 50 female), and 86  Malaysian Indian  (36 male, 50 female). This study excluded subjects of mixed race, those with craniofacial deformities, and those who had previously received orthodontic treatment or had face surgery. The results showed that the golden ratio had no significant association with physical attractiveness. [ 367 ] [ 368 ]


Some argue that body type preference is a mark of culture and regional beauty standards, and that there is no definitive "ideal body" for women, because it constantly shifts. [ 369 ] [ 370 ] [ 371 ]  Some authors argue that body types have never been universal and that most  evolutionary psychology  studies on the "ideal female body" shape have been questioned or disproven due to external factors such as unreliable data and idealized western  gender roles . [ 372 ] [ 373 ] [ 374 ] [ 375 ]    On the internet, communities can create their own niche beauty standards that differ from the cultural norm. [ 376 ] [ 377 ] [ 378 ]  It has been argued that the "perfect body" is a matter of personal preference and exposure to regional media. [ 379 ] [ 380 ]


Physical intimacy  is  sensuous   proximity  or touching. It is an act or reaction, such as an expression of  feelings  (including close  friendship ,  platonic love ,  romantic love , or  sexual attraction ), between people. Examples of physical intimacy include being inside someone's  personal space ,  holding hands ,  hugging ,  kissing , caressing and  sexual activity . [ 1 ]  Physical intimacy can often convey the real meaning or intention of an interaction in a way that accompanying speech cannot do. Physical intimacy can be exchanged between any people but as it is often used to communicate positive and intimate feelings, it most often occurs in people who have a preexisting  relationship , whether familial, platonic or romantic, with romantic relationships having increased physical intimacy. Several forms of romantic touch have been noted including holding hands, hugging, kissing, cuddling, as well as caressing and massaging. Physical affection is highly correlated with overall relationship and partner satisfaction. [ 2 ]


It is possible to be physically intimate with someone without actually touching them; however, a certain  proximity  is necessary. For instance, a sustained  eye contact  is considered a form of physical intimacy, analogous to touching. When a person enters someone else's personal space for the purpose of being intimate, it is physical intimacy, regardless of the lack of actual physical contact.


Most people partake in physical intimacy, which is a natural part of interpersonal relationships and  human sexuality , and research has shown it has health benefits. A hug or touch can result in the release of the hormone  oxytocin  and in a reduction in stress  hormones . [ 3 ]  Massages, stroking and cuddling have furthermore shown that they have widespread beneficial effects on well-being. The most pronounced effects can be found for a reduction of pain as well as feelings of depression and anxiety. However, also blood pressure and momentary mood can be improved through physical touch. [ 4 ]


Due to the important role that language-based communication plays in humans, the role of touch is often downplayed; however, there is ample evidence that physical touch still plays an important role in everyday human relationships. While humans often communicate verbally, they also participate in close contact. Physical touch has emotional and social connotations that often far outweigh anything that can be expressed via language. [ 5 ]


Inducements towards physical intimacy can come from various sources. During colder seasons, humans as well as other animals seek physical intimacy with one another as a means to apportion thermoregulation. [ 6 ]  Some forms of physical touch among monkeys and apes serve multiple functions, including cleaning, treatment of a lice influx or infection and social grooming. [ 7 ]


Some forms of physical intimacy may be received negatively. This attitude is especially marked amongst those with  haphephobia . [ 8 ]  One study has shown that there is generally a higher level of physical intimacy allowed between  immediate family  members than between  second-degree relatives . [ 9 ]  Intimacy norms are usually more negative near  erogenous zones . Some jurisdictions may specify this as referring to the  genitals ,  buttocks  and female  breasts . [ 10 ]


Physical affection and intimacy appear to have a profoundly important role during infancy and childhood. The skin is the largest sensory organ and is the first to develop. Humans experience touch as early as fetal development, when the fetus begins receiving sensory information from coming in contact with the mothers' abdominal wall. In infancy, babies receive significant amounts of touch through being held, cuddled, and breastfed. In addition to necessary functions like breastfeeding, touch is also used to soothe and calm babies or with skin-to-skin contact called "kangaroo care". [ 11 ]  Vision and auditory senses are limited in infancy and babies are introduced to their world primarily through touch and are able to distinguish between temperature and texture. [ 12 ]


Decreased amounts of affectionate touch from caregivers (i.e. for infants in institutional settings or infants with depressed mothers) is related to cognitive and neurodevelopmental delays. [ 13 ]  These delays appear to persist for years and sometimes whole lifetimes. [ 14 ]  Studies suggest that if depressed mothers give their infants massages, it benefits both the baby and themselves, increasing growth and development for the babies and leading to increased sensitivity and responsivity of the mothers. [ 15 ]  There are also biologically beneficial effects of infant massage, with premature infants displaying lower cortisol levels after being held by their mothers. During the holding period, the mothers' cortisol levels also decreased. [ 16 ]


Most people value their  personal space  and feel discomfort,  anger  or  anxiety  when somebody encroaches on their personal space without consent. [ 17 ]  Entering somebody's personal space is normally an indication of familiarity and intimacy. However, in modern society, especially in crowded urban communities, it is at times difficult to maintain personal space, for example, in a crowded  train ,  elevator  or street. Many people find the physical proximity within crowded spaces to be psychologically disturbing and uncomfortable. [ 17 ]  In an impersonal crowded situation, eye contact tends to be avoided. Even in a crowded place, preserving personal space is important. Non-consensual intimate and sexual contact, such as  frotteurism  and  groping , are unacceptable.


On the other hand, most people occasionally desire physical proximity to others, and will at times welcome a familiar and trusted person into their personal space. When a partner or friend is not available at such a time, some people satisfy this need for human contact in a crowded venue, such as a  bar ,  nightclub ,  rock concert ,  street festival , etc.


People who are on a  familiar basis  may enter into each other's personal space to make physical contact. These can be indicators of affection and trust. The manner in which people display affection is generally different in a public context to a private one. In private, people in an  intimate relationship  or who are familiar with each other may be at ease with physical contact and displays of affection, which may involve:


Bonding through intimate, non-sexual contact between platonic friends and family members includes, but is not limited to, holding hands, hugging, cuddling, and kissing on the cheeks.


In public, however, and depending on the nature of the relationship between the people, a  public display of affection  is generally constrained by  social norms  and can range from a gesture, such as a  kiss  or  hug  in greeting, to an embrace or  holding hands . Maintaining  eye contact  can be regarded socially and psychologically as analogous to touching.


The role of touch in interpersonal relationships across development and in different cultures is understudied, however, some observational data suggests that in cultures who engage in more physical intimacy have lower rates of violence, demonstrated in adolescents and children. [ 18 ]  Peoples living nearer to the equator (Mediterranean, central and South America, Islamic countries) tend to have high-contact social norms, whereas countries further from the equator tend to be lower contact (northern Europe, North America, northeast Asian). The public display of interpersonal touch and intimacy appears to vary across cultures as well. [ 19 ]


The term "skinship"  ( スキンシップ ,  sukinshippu )  originated as a  pseudo-English  Japanese word ( wasei-eigo ), which was coined to describe the intimacy, or closeness, between a mother and a child. [ 20 ] [ 21 ] [ 22 ]   Today, the word is generally used for bonding through physical contact, such as holding hands, hugging, or parents washing their child at a bath. The term has been promoted by pediatrician and developmental psychologist  Nobuyoshi Hirai  (平井信義), and he mentioned it was taken from a term coined by an American woman at a  WHO  seminar held in 1953. [ 23 ]  The earliest citation of this word appears in  Nihon Kokugo Daijiten  in 1971. [ 24 ]  According to Scott Clark, author of a study of  Japanese bathing culture , the word is a  portmanteau  combining "skin" with the last syllable of "friendship". [ 25 ]  The similarity with the English word ' kinship ' suggests a further explanation. [ 22 ]  Use of the word "skinship" in English publications seems to focus on the notion of sharing a bath naked, an idea known in Japanese as "naked association"  ( 裸の付き合い ,  hadaka no tsukiai ) . [ citation needed ]  It is not clear why the meaning shifted to the parent–child relationship when  borrowed back  into English. This word is also used in  South Korea . [ 26 ]  The term is now described in  Oxford English Dictionary  as a part of Korea-related update in 2021. [ 27 ]


Some animals participate in behaviors similar to physical affection in humans. Called social grooming or allo-grooming, these behaviors are less common outside of primates, while other species do perform these behaviors, primates seem to spend much more time doing this compared to other animals. Some species devote as much as 20% of their day to grooming behaviors, much of which is spent grooming others, rather than themselves. [ 28 ] [ 29 ]  In more social species the amount of time spent in self grooming is much less than the time spent in social grooming. While these behaviors may appear to be for the purpose of hygiene (i.e. removal of parasites, fur cleanliness, etc.), evidence suggests that grooming behaviors perform a unique social function which facilitates bonding. [ 28 ]  From an evolutionary perspective, the amount of time being devoted to allo-grooming appears to exceed the amount of time in which it would be adaptive, therefore underscoring the idea that grooming must have a purpose beyond hygiene maintenance. Furthermore, there are core grooming partnerships which remain quite stable and do not change frequently, sometimes with the same partners on the timescale of years. [ 30 ]


Some argue that grooming is something which is exchanged like a service with the expectation that equal amounts of time will be spent or reciprocated by their grooming partner. [ 31 ]  Primates tend to groom each other equal amounts of time or with the expectation that they will be reciprocated with defense in a dangerous situation. Primates who spend more time grooming each other are more likely to defend each other when attacked. Although it is not clear how this effect is brought about, in all likelihood it is the protective effect that known relationships have: more dominant animals are less likely to attack or harass an individual who is known to have grooming partners who might come to its aid. However, the likelihood of a female going to the aid of another female when the latter is under attack is significantly correlated with the amount of time the two of them spend grooming with each other. [ 32 ]  A more plausible interpretation is that grooming provides the psychological underpinning for an individual's willingness to offer subsequent support. [ 33 ]  It does this not by offering a direct exchange of benefits, but rather by creating the psychological environment that allows support to be traded mutually.


The  PLISSIT model , also known as the  PLISSIT model of sex therapy , [ 1 ]  is a  modeling system  used in the field of  sexology  to determine the different levels of  intervention  for individual clients. The model was created in 1976 by  Jack S. Annon . The letters of the name refer to the four different levels of intervention that a sexologist can apply:  permission  ( P ),  limited information  ( LI ),  specific suggestions  ( SS ), and  intensive therapy  ( IT ). The model is also used outside the field of sexology, especially in fields involving extensive or life-threatening surgery. [ 2 ]


The model created by Annon has four levels of increasing intervention and interaction related to what kind of and how much help is given to a client. The varying levels largely revolve around what the client is looking for and how comfortable they are in discussing  sexuality  and  sexual health . [ 2 ]


The first level is  permission , which involves the sexologist giving the client  permission  to feel comfortable about a topic or permission to change their lifestyle or to get medical assistance. This level was created because many clients only require the permission to speak and voice their concerns about sexual issues in order to understand and move past them, often without needing the other levels of the model. The sexologist, in acting as a receptive,  nonjudgmental  listening partner, allows the client to discuss matters that would otherwise be too embarrassing for the individual to discuss. [ 3 ]


The second level is  limited information , wherein the client is supplied with limited and specific information on the topics of discussion. Because there is a significant amount of information available, sexologists must learn what sexual topics the client wishes to discuss, so that information, organizations, and  support groups  for those specific subjects can be provided. [ 3 ]


The third level is  specific suggestions , where the sexologist gives the client suggestions related to the specific situations and assignments to do in order to help the client fix the  mental  or  health problem . This can include suggestions on how to deal with sex related diseases or information on how to better achieve  sexual satisfaction  by the client changing their sexual behavior. The suggestions may be as simple as recommending exercise or can involve specific regimens of activity or medications. [ 4 ]


The fourth and final level is  intensive therapy , which has the sexologist refer the client to other  mental  and medical health professionals that can help the client deal with the deeper, underlying issues and concerns being expressed. This level, with the onset of the  internet age , may also refer to a sexologist suggesting professional online resources for the client to browse about their specific issue in a more private setting. [ 5 ]


The  PLISSIT model  was extended in 2006 by  Sally Davis  and  Bridget Taylor  because of concerns that practitioners often bypass permission-giving and go straight to providing information (sometimes merely in the form of a leaflet), without giving patients the opportunity to express any concerns they might have. The extended model, named the  EX-PLISSIT model , places permission-giving at the core. By giving people explicit permission to discuss any concerns they have about their sexuality, the healthcare professional affirms the individual as a sexual being. Any information or suggestions that follow, are then specific to the needs of that person. [ 2 ]


The EX-PLISSIT model also requires further permission-giving in the form of 'review', whereby the healthcare professional asks the patient to review the interaction and is given the opportunity to express any further worries or concerns. In addition, this model requires the professional to reflect on their interactions, challenging assumptions and extending their knowledge. [ 2 ]


Premarital sex  is sex before marriage. Premarital sex is sex between two people who are not married to each other. Premarital sex is considered a  sin  by a number of  religions  and also considered a  moral issue  which is  taboo  in many  cultures . Since the  Sexual Revolution of the 1960s , it has become accepted by certain liberal movements, especially in  Western countries . A 2014  Pew study  on global  morality  found that premarital sex was considered particularly unacceptable in " Muslim  Majority Countries", such as  Malaysia ,  Jordan  and  Pakistan , each having over 90% disapproval, while people in  Western European  countries were the most accepting, with  Spain ,  Germany , and  France  expressing less than 10% disapproval. [ 2 ]


Until the 1950s, [ 3 ]  "premarital sex" referred to sexual relations between two people prior to marrying each other. [ 4 ]  During that period, it was the norm in Western societies for men and women to marry above the age of 21, and there were no considerations that one who had sex would not marry. The term was used instead of  fornication , which had negative connotations, [ 3 ]  and was closely related to the concept and approval of  virginity , which is  sexual abstinence  until marriage.


The meaning has since shifted to refer to any sexual relations a person has prior to marriage and removing the emphasis on the relationship of the people involved. [ 4 ]  The definition has a degree of  ambiguity . It is not clear whether sex between individuals  legally forbidden from marrying  or the sexual relations of one uninterested in marrying would be considered premarital. [ 3 ]


Alternative terms for premarital sex have been suggested, including  non-marital sex  (which overlaps with  adultery ),  youthful sex ,  adolescent sex , and  young-adult sex . These terms also suffer from a degree of ambiguity, as the definition of  having sex  differs from person to person. [ 3 ]


In modern Western cultures, social value of  sexual abstinence  before marriage has declined. Historically, a significant portion of people had engaged in premarital sex, although the number willing to admit to this was not always high. In a study conducted in the United States, 61 percent of men and 12 percent of women born prior to 1910 admitted to having premarital sex; this  gender disparity  may have been caused by cultural double standards regarding the admission of sexual activity, or by men frequenting  prostitutes . [ 3 ]


Starting in the 1920s, and especially after  World War II , premarital sex became more common, particularly among women. By the end of the 20th century, between 75 and 80 percent of Americans had experienced sexual intercourse before the age of 22. This has been attributed to numerous causes, including the increasing median age at marriage and the widespread availability of efficient  contraceptives . [ 3 ]


According to a 2001  UNICEF  survey, in 10 out of 12 developed nations with available data, more than two-thirds of young people have had sexual intercourse while still in their teens. In Denmark, Finland, Germany, Iceland,  Norway , the United Kingdom and the  United States , the proportion is over 80%. In Australia, the  United Kingdom  and the United States, approximately 25% of 15-year-olds and 50% of 17-year-olds have sex. [ 5 ]  In a 2005  Kaiser Family Foundation  study of US teenagers, 29% of teens reported feeling pressure to have sex, 33% of sexually active teens reported "being in a relationship where they felt things were moving too fast sexually", and 24% had "done something sexual they didn't really want to do". [ 6 ]  Several polls have indicated  peer pressure  as a factor in encouraging both girls and boys to have sex. [ 7 ] [ 8 ]


A majority of Americans have had premarital sex, according to a 2007 article in Public Health Reports. This is true for current young adults and also young adults in the late 1950s and early 1960s. Data from the National Survey of Family Growth indicate that in 2002, 77% of Americans had sex by age 20, and of that percent, 75% had premarital sex. Of women who were born between 1949 and 1978, approximately 91% had premarital sex by age 30, and of women who were born between 1939 and 1948, 82% of them had had premarital sex by age 30. [ 9 ]


When comparing the General Social Survey of 1988–1996 to the one of 2004–2012, researchers found that participants of 2004–2012 did not report more sexual partners since the age of 18, nor more frequent sex or sex partners during the past year than those respondents of the previous survey. There appears to be no substantial change in sexual behavior contrasting the earlier era to the current one. Current-era respondents were more likely to report having sex with a casual date or friend than reporting having sex with a spouse or regular partner. [ 10 ]  From 1943 to 1999, young women's approval towards premarital sex increased from 12% to 73%, and from 40% to 79% among young men. The percentage of people who felt  guilt around premarital sex also decreased during this period. As of 2005, less than 25% of people believe premarital sex is “always or almost always” wrong. [ 11 ]


Within the United States, a  cohort study  of young adults in university found that men self-report more permissive attitudes about casual sex than women. [ 12 ]  Another study found university students can be grouped by their ideal relationships—those who express a desire for sex exclusively in a committed partnership have fewer hookups and "friends with benefits" partners than those categorised as desiring "flexible" relationships and recreational sex. [ 13 ]


A 2006 study that analysed the  Toledo Adolescent Relationships Study  found that more boys report having non-dating sexual partners than girls. Of this sample, a third of boys only have had sex with their romantic partner. A third of boys who have had sex with a partner they are not dating within the past year wished for the girl to be their girlfriend. [ 14 ]  Many young adults are more likely to engage in sex with romantic partners than with casual acquaintances or "friends with benefits." [ 15 ]


A 2011 study that surveyed young adults about their emotional reactions after premarital sexual encounters found that men reported more positive and fewer negative emotional reactions, and both men and women reported that the experience was largely more positive than negative. [ 16 ]  Women reported that condom use was associated with fewer positive and more negative emotional reactions, and for men condom use was associated with fewer negative emotional reactions. [ 16 ]  A 23-year study in a Human Sexuality class investigated gender differences in men and women's reactions to their first sexual experience. In the earlier years of the study, men reported more pleasure and greater anxiety than women, while women reported more feelings of guilt than men. Cohort studies carried out over 23 years found that in later years, women expressed greater pleasure and less guilt. The differences between emotional reactions among men and women decreased slightly during the 23 years. [ 17 ]  Such decreases in differences to first sexual intercourse may be a result of the increasing normality of premarital sex in America. An international online sex survey compared responses of residents of 37 countries against World Economic Forum figures for gender equality in those countries, finding that countries with high gender equality had respondents report more casual sex, a greater number of sex partners, younger ages for first sex, and greater tolerance of premarital sex. [ 18 ]


In some countries, gender differences with premarital sex can be linked to virginity. In India, a woman may undergo a " virginity test " on her wedding night where she can be banished by her husband or subject to an honor killing if found she is no longer a virgin. Men are not subjected to this same test and could get away with having premarital sex. [ 19 ]  In Iran, if a husband finds out his wife had premarital sex, it can be used as grounds for divorce. Therefore,  hymen reconstruction  surgery is not uncommon for women who wish to prove their virginity. [ 20 ]


Different ethnic and cultural groups in America have varied religiosity and sexual attitudes. A study with college participants found that Asians had more conservative sexual attitudes compared to Hispanics and Euro-Americans. Hispanics reported sexual attitudes similar to that of Euro-Americans. Asian, Hispanic, and Euro-American women with high levels of spirituality were found to have a correlation between conservative sexual attitudes and perceived religiosity. Religiosity and religious fundamentalism most strongly predicted conservative sexual attitudes in Euro-Americans and Asians. [ 21 ]


In the  Indian  city of  Mumbai , research showed that among college-age students, 3% of females affirmed having premarital sex and 26% of males affirmed having premarital sex. [ 22 ]  Population Council, an international NGO, released a working report in 2006 showing similar statistics nationally in India, with fewer than ten percent of young females reporting having had premarital sex, compared with 15% to 30% of young males. [ 23 ]  In  Pakistan , 11% of men were reported as having participated in pre-marital sex, although a greater percentage, 29% reported having participated in non-marital sex. [ 24 ]


People who have premarital sex are recommended by health professionals to take precautions to protect themselves against  sexually transmitted infections  (STIs) such as  HIV/AIDS . [ 25 ]  There is also a risk of an  unplanned pregnancy  in  heterosexual  relationships. [ 26 ]  Around the world,  sex education  programs are run to teach school students about  reproductive health ,  safe sex ,  sexual abstinence , and  birth control .


Sexual activity among unmarried people who do not have access to information about reproductive health and birth control can increase the rate of  teenage pregnancies  and contraction of  sexually transmitted infections . The rates of teenage pregnancy vary and range from 143 per 1000 girls in some sub-Saharan African countries to 2.9 per 1000 girls in South Korea. The rate for the United States is 52.1 per 1000, the highest in the developed world, and about four times the European Union average. [ 5 ] [ 27 ]  The teenage pregnancy rates between countries must take into account the level of general  sex education  available and access to contraceptive options.


Views on premarital sex are often shaped by religious teachings and beliefs, in part because ancient religious texts forbid it. [ 28 ] [ 29 ]  People who actively practice religion are less likely to engage in premarital sex or at least go longer before having sex for the first time. [ 28 ] [ 29 ]   Evangelical Christian  young adults (ages 15 through 22) who are never married are much less likely to engage in premarital sex if they attend  church services  on a weekly basis, compared to those with no  church attendance . [ 30 ]  Additionally, among Christians who have never been married, those who consider religion to be "very important" engage less in premarital sexual intercourse than those who view religion as "somewhat important". [ 31 ]  Those young adult Christians who belong to  conservative denominations  (e.g.  Conservative Mennonites ) are less likely to engage in premarital sex than those who are  members  of mainline churches. [ 32 ]