We were doing so well right up until the chapter about how activity and fitness level is more important than thinness, that thinness can't actually tell you anything about a person's activity level or health, but being fat is still bad, so you should probably stop that, even though exercise probably won't make you thin, either. Sigh.
Ignore the food and body size commentary (and the handful of "funny" asides about women being one way and men the other, isn't it funny how they're sooooo different and men being like women in any way is degrading and hilarious?!); read the sciency bits. Pretty interesting, with a few dollops of "you've got to be shitting me."