Why can we become "heavier"?
369634
We appear heavier if we  take a posture that requires the "lifter" to use their strength to not only lift us but to "bundle" us or shape us into a position or form that is liftable. If we are uncooperative, the lifter must do two tasks, and must divide their strength between the tasks, leaving less strength for the lifting alone.
938395
Muscle is heavier than fat, don't go by your weight.
1165464
Well, actually, your theory is very similar to that of the Theory of Relativity, or something. If you slowed down time by moving faster, the objects would literally gain weight. (Fat people, plz do not go on space missions...) And once you were travelling at the speed of light, you would have infinite weight. (But of course, your MASS would still be the same. So fat people should let out a big breath.) I'm not sure exactly which theory this is...
665983
It's called gaining mass to lose the as*.
946538
People gain weight for different reasons.  Some may simply be lazy and not care about their health or physical appearance.  Others may be depressed and use food as a comfort zone.  Others again may intentionally put on weight to make themselves unattractive to others so they are not hurt by a relationship going wrong(usually as a response to being hurt in the past)\n\nIt really depends on what their priorities and motivations are.  If they don't make their health and appearance a primary priority ultimately it will suffer.  Also note that it's one thing to be thin, it's entirely another to be healthy and fit.  You shouldn't link the two of them together.\n\nEdit/Addition: Actually numerous people here have answered your question.  It's not easy to just flick a switch in your head and reverse or change the things that are causing you to overeat or not exercise.  If it is a deeply traumatic issue that you have trouble dealing with usually it takes a LOT of work and a lot of motivation to break out of it.  The answer to your question is threefold:\n\n1. Some people are too emotionally depressed to make a change for the better and hence continue along the same self-destructive path OR\n2. They're medically ill and cannot help it (quite a rare case compared to the other 2 OR\n3.  They're too lazy\n\nHope that clears it up
335958
If you are working out, you will get new muscles. Muscles weigh more than fat. That is why your weight isn't a good weigh to tell if you are healthy. It's good that you have quit smoking though.
521104
A question not a lot of people ask, but this is a good one.  There is sometimes a problem with the hypothalamus, which sets your body's weight.  Most often it is higher than we would like, but sometimes it is lower.  There is a juice that is a modifier.  It helps heavier people loose, but more importantly for you, it stimulates underweight bodies to gain.  It modifies blood sugars for some afflicted with type l and even more potently affects people with joint injuries by modifying anti-inflamationenzymes.
817667
Well, i heard this on oprah.  If you trying to gain weight go on  diet for a little bit and then suddenly stop.  The shock will cause you body to pack on some extra pounds.
753156
Bets,\n\nA part of the reason why you gained weight is because your metabolism slowed down.  This is typical of college students (going from teens to 20s).\n\nJust bump up your cardio to burn off what you drink.\nLift weights to make your body denser.
646742
Muscle is heavier than fat.
234625
because you  exercise and lift weights ??... you  big strong   guy you...lol...
423760
You are the "perfect" weight if you go by the medical standard that for every 5 ft you should be 100lbs.  Why do you feel you should be 5-10lbs lighter?  Just the number or do you want to be firmer, more fit?  You can up your exercise to become more lean, increasing your muscle mass.  I'm 5'1" and 114 (just weighed today at doc's) and I would like to be down 9-14lbs, but if I increase my muscle and lose some fat, even staying at the same weight, I'll look and feel better for myself.
330598
When they say muscle weighs more than fat, they are referring to its density. Muscle is denser, and therefore it takes less of it to reach the same weight as an amount of fat
243360
Well, I think the reason we put on weight over winter is because most people do not want to go outside in the freezing cold weather.  Think about it, who wants to go outside in 35 degree weather and run five miles? Nobody I know! I think you could prevent this from happening is eating foods that are not very high in fat, and going to the gym and doing things that you would do outside inside (i.e. track etc).  You can also get workout material in your house like weights and all in one gyms. Another thing that might help is if you are unable to attend a gym, or don't have a all in one gym at your house, go on a specialized diet for the winter and eat specialized foods.  I heard a lot of people get help from those.  I hope I helped!
44204
No, living things 're'turn to dust, meaning that the net weight gain is 0.  The Earth's mass does increase slightly (relative to the size of the Earth) from all of the space dust and meteors that constantly burn up in the atmosphere and fall to the ground.
130058
Gaining weight can be the result of many things. Most of the time, weight is gained by stress. If you have been under extreme stress or pressure, that can cause weight gain.
359524
You gained more muscle which is heavier than fat and by working on your legs through walking, you've gained heavier muscle.  Gaining leg muscles produce more weight than any other muscle in your body.\n\nYou should feel better and your body should feel firmer.  You replaced your fat with healthy muscles.  Don't worry about the weight.  If you want to trim the weight down, eat sensibly.  That always does the trick.