Instruct: Classify Amazon reviews into positive or negative sentiment
Query: this is not based on science.

The premise for this book is not based on any science that is accepted as true. As a physician, I can tell you that there is no difference between blood groups as far as diet effectiveness goes. The difference between blood types is so minute, we are talking tiny 6 carbon sugar molecule differences between A,B,O. Take a step back and think about this logically and I think you will realize that is completely fictitious and not worth the paper it is printed on. If you must do a fad diet, pick anything other than this! If you actually want to lose weight, be healthier, and live longer you will have to start eating right regularly and exercising.