It isn't clear at all. a) Humans are spectacularly efficient at turning solar energy into bioavailable calories. This impacts virtually every animal. b) Lab a

It isn't clear at all. a) Humans are spectacularly efficient at turning solar energy into bioavailable calories. This impacts virtually every animal. b) Lab and zoo diets have dramatically changed. For instance in the lab there was a change from specific portioned diets to the notion that food should always be provided. Any study that claims that there was some mysterious rise in obesity is simply lying. And again there is a push for controlled, restricted diets because having sedentary rats and mice who can eat whenever they want is yielding unhealthy subjects. c) The study this article links was lead by a guy who is an advisor to Coca-cola, Kraft, Frito-Lay, the Restaurant Association, among others. It is a profoundly corrupt industry, and yeah the notion that some mysterious unknown cause is to blame is convenient in that situation.