The story of my sister, who was fat because of genetics but somehow magically lost weight when put on a strict diet. Growing up, my sister was always fat. Next to kids today she'd probably be labeled anorexic, but back then she stood out. Mom always said it was just genetics. She wasn't fat, she was husky, like my dad. (No, actually, he was fat too.) Mom and I were skinny. At doctor's visits they would always recommend my sister watch her food intake, but it never happened. My sister picked up the "genetics" argument and used it. One example: In high school, the day after we went shopping my sister got a package of cheese out of the fridge. One of these on the left: http://i.imgur.com/asacE54.jpg I love cheese, and I planned on snacking on it over the course of several days. Well, she cut up the entire thing and had it on her plate to eat at once and couldn't understand why I was so angry when I caught her. She seriously thought it was acceptable to cut up a family sized chunk of cheese and eat it all in one sitting. Besides being selfish as hell because I'm sure the rest of us would have liked to snack on it too, WTF? How many calories is that? Maybe someone will do the math.  Anyway, she steadily got fatter as we entered our 20s. She's 5'2 or 5'3 and last I knew her weight she was 210 at least. Next thing we know, she'd had a stoke and spent a few days in the hospital. The doctor, as part of her treatment, put her on a very strict diet. No candy, no fast food, etc.  Well...wouldn't you know it after that every time I saw her she looked less fat. Now I expect her to be human sized in another month or two. She also says she feels better. She doesn't get as tired just walking around and her bones and joints don't ache anymore. I guess changing her diet messed with her genetic make-up somehow!