[kenjackson]

I think a big difference with obesity is that the obese may not exhibit any external behavioral difference. That is an obese person may eat the same amount of food (and same foods) as a non-obese person.

Being obese is probably more like not being good at math, than a heroine addiction. People who aren't good at math could probably use more work at math. Yet, just because they read the same books as Terrence Tao -- don't expect the same result.