- "What is causing it is very difficult to know."
With no development of this idea he falls back on the traditional line,
- "It is entirely possible that the calorie density of food and portion sizes could be higher."
As a paleo eater who chows down without restriction on lots of fat, meat and vegetables and takes part in only episodic strenuous exercise, I can only imagine how hard the future of these kids will be. They will be encouraged to eat a lot less than me, and probably be forced to do more.