Raw Food: Meant for Us or Not?

Hello,

I wanted to follow up on something that was mentioned today in class. Robin brought up the "raw food" diet fad that has experienced popularity -- the idea behind it is that humans should only eat raw food like the rest of the animal kingdom. Many people lose weight when they begin a raw-food diet, but is that because raw food is better for our bodies... or worse?

Primatologist Richard Wrangham holds that the reason why the neanderthals died out and our ancestors did not is precisely because early humans had learned how to cook, giving them an evolutionary advantage over neanderthals. Wrangham gives two main reasons:

1) Once food is cooked, our digestive tract is able to absorb a lot more of the nutrients from the food. If primitive man cooked their food regularly, their diet became a lot more nutritious, which in turn gave their brains the energy supply they needed to grow into the massively complicated organs found in today's humans.

2) Not only is cooked food better for us, but we have an easier and quicker time eating it, too. Modern primates spend a lot of time tearing off and chewing on tough, raw food -- Wrangham estimates the time spent at half a day! Once our ancestors had more free time, they could put those large brains of theirs to work thinking about other tasks, such as agriculture, tool-making, and developing a social culture.

Because they had mastered the art of cooking, primitive humans, with their large brains and the time to fool around with them, successfully edged out neanderthals in the race to the top. I am led to agree that cooking has been part of our life for a long time, especially once the structure of our bodies is compared to that of our closest relative, the chimpanzee.

Our teeth and jaw are much smaller, indicating that our diet is softer and more tender than what chimps have to munch on (assorted fruit, raw plant matter, insects, and meat, in descending order). Our digestive tract is shorter, so if a human ate the exact same food as a chimp, he would not get as much nutrition out of it -- unless the food was prepared in some way to make it more easily digestible. And as was mentioned earlier, our brains are obviously larger, which means our diet has to be high in energy if that organ is to be supplied with ample energy.

Since the types of food we primates have always eaten is roughly the same in type and proportion, something else must have happened a long time ago that allowed humans to extract more value from the food they ate. That "something" was the day early humans started learning how to cook their food.

Wrangham's interview on NPR's weekly "Science Friday" program is available online. If you don't want or don't have time to listen to the podcast, here is a short article which sums up his position.

-- Jenny