I agree with you there. Obesity is a sign of a more-than-adequate diet, and a higher intake of protein, especially in Western civilization goes with that, along (of course) with the higher levels of simple carbohydrates that lead to obesity. A diet higher in protein leads to increased growth rates, and better immunity--not things to be avoided.
No they are not. But nothing has only one side. Increased growth rates mean an earlier onset of menarch and with that an earlier interest in....other things. Personally I think all this stuff about chemicals, hormones, and mares placentas are a bunch of hogwash. American kids get access to more high quality animal and plant proteins than any other society on the planet. Hell, they get more protein than almost any society in history.
It's no wonder they mature faster and grow larger than their parents. One need only look at the children of immigrants to see the evidence.
L