World History of Food and Nutrition

I have a theory about the link between population evolution and nutrition
It seems that the people most aquainted with “power foods” were, in history, the most quick to evolve and conquer.
Where does the strenght of a nation lie, if not in their kitchen.

I am asking for a hand now… does anyone know any website that could help me find the information to sustain “academically” this ideea ?
And second, if Michael Winn is online, what is his oppinion about it.

Thank you

E.