BOB HIRSHON (host):
The benefits of cooking…I’m Bob Hirshon and this is Science Update.
Humans have larger brains and bodies than our closest relatives, and we’re more active. All this takes a lot of energy, and many scientists think these adaptations were made possible by a switch to a meat-rich diet around 2 million years ago. But that only tells part of the story, according to Harvard evolutionary biologist Rachel Carmody and her colleagues. They recently found that mice fed a diet of meat or sweet potatoes gained the most weight if the food was cooked.
RACHEL CARMODY (Harvard University):
Cooking would have enabled ancestral humans to extract more energy from key foods in their diet, even if non-thermal processing methods like pounding were already in use.
She says cooking begins the process of digestion, allowing us to extract more energy from food. It also keeps our gut bacteria from hoarding the energy for themselves. And finally, cooked food cuts down on food food-borne illnesses, which take a lot of energy for the body to fight. I’m Bob Hirshon, for AAAS, the science society.