"Raw-foodism is a good way to lose weight," Dr. Wrangham writes. He is a professor of biological anthropology at Harvard University, the curator of primate behavioral biology at the Peabody Museum, and the director of the Kibale Chimpanzee Project in Uganda.
All of the studies of the body weight of raw-foodists have found that they tend to be thin. Maybe this is why the participants in the raw food diet program that Gabriel Cousens, M.D., developed did so well in controlling their diabetes. The film "Simply Raw," which I reviewed positively here last year, focuses on the experiences -- both positive and negative -- of six people with diabetes from around the country who took this program. Simply losing weight goes a long way toward diabetes control.
Raw-foodists report a sense of well-being, better physical functioning, less pain, more vitality, and improved emotional and social performance. Researchers have found improved serum cholesterol and triglyceride values. Raw foodists, unlike people who cook their food, also don't need to be concerned about the Maillard reaction, which we know as advanced end products (AGEs).
On the other hand, raw diets cause health problems. They include low bone mass in the back and hips, low levels of vitamin B12, low levels of the good HDL cholesterol and high levels of homocysteine, which may cause heart disease.
Those side effects don't show up right away. But others do. Eating nothing but raw food can make you pee a lot. The participants in studies of raw food diets were constantly hungry. Still, the basic problem with a raw food diet is that it doesn't give us enough energy, Dr. Wrangham concludes.
All of us can appreciate how cooking makes our food safer, improves the taste of our food, and reduces spoilage. It lets us open, cut, or mash tough foods. But few of us appreciate the key benefit, that cooking increases how much energy we get from food.
Other animals don't need cooked food. We do.
In the past anthropologists differentiated humans from other animals by calling us "Man the Tool-Maker," "Man the Hunter," and "Man the Meat Eater." Dr. Wrangham says the evidence suggests that "Man (and Woman) the Cook" came first.
Our bodies started to change about 1.8 to 1.9 million years ago. That's when Homo erectus emerged from its australopithecine ancestors and began to master fire and started to cook much of its food.
"After our ancestors starting eating cooked food every day," Dr. Wrangham writes, "natural selection favored those with small guts, because they were able to digest their food well, but at a lower cost than before. The result was increased energetic efficiency."
While we have smaller intestines than any other primates near in size to us, this is hardly all. We also have small mouths, small lips, weak jaws, small teeth, and small stomachs. Unlike the apes, we don't need these large body parts.
The energy trade off of a smaller digestive system means that we can have something that requires a disproportionate amount of energy, our big brains. All this and more because our ancestors learned to cook our food.
Now, all this is but the briefest summary of the case that Dr. Wrangham offers. I highly recommend that you read his new book.
If all you want to do is lose weight, you might consider a raw food diet. Personally, I prefer to preserve my energy too.