3.5 Million years Ago Diet Changed

Why modern man is fat and how to change it

Early Diet may be Clue to weight loss

A new analysis of early human teeth from extinct fossils has found that they expanded their diets about 3.5 million years ago to include grasses and possibly animals. Before this, humanlike creatures - or hominins - ate a forest-based diet similar to modern gorillas and chimps. For more information on Weight loss and diets, see Video below.
Australopithecus - Wiki Article