Biologists, evolutionary psychologists and anthropologists point to our hunter-gatherer ancestry to explain much of human behaviour today. But what if the roots of humanity lie not broadly in adaptation to nature but strongly influenced in adapting to a communal life cooking food? That is what Richard Wrangham, a Harvard-based biological anthropologist proposed in his book Catching Fire—how cooking made us human. Since this book was published in 2010, I have used many of the arguments presented by Dr Wrangham to assist people who come to my clinic for help in overcoming their ill health. His ideas are withstanding the test of time. I highly recommend reading this book and examining from an historical perspective why cooking food is better for your health than eating raw food.
Catching Fire
Catching Fire is an easily understandable scientific essay that expands our understanding of human evolution, through ‘a cooking hypothesis’. Dr Wrangham states, “Cooked food does many familiar things. It makes our food safer, creates rich and delicious tastes and reduces spoilage. Heating can allow us to open, cut or mash tough foods. But none of these advantages is as important as another aspect: cooking increases the amount of energy our bodies obtain from food. The extra energy gave the first cooks biological advantages. They survived and reproduced better than before. Their genes spread. Their bodies responded by biologically adapting to cooked food, shaped by natural selection to take maximum advantage of the new diet. There were changes in anatomy, physiology, ecology, life history, psychology and society”.
Richard Wrangham writes that eating cooked food, whether meat or plants or both, makes digestion easier, provides more energy, renders many natural plant poisons inactive, and generally takes less time to eat than raw foods. Over 1.6 million years, the large amount of energy that was formerly spent on attempting to digest raw foods was made available through cooking, to power our increasing brains. The warmth provided by fire enabled us to shed most of our body hair, enabling us to run farther and hunt more without overheating. So the simple expedient of cooking food gave our ancestors access to many more ‘safe’ calories every day, which allowed early humans survival quality over competing animals in times of limited resources.
Dr Wrangham suggests that our ancestors mostly eliminated the normal primate behaviour of eating foods where they were located, and adopted social eating behaviour around a fire. The protection that fire provided at night enabled our ancestors to sleep on the ground. Females adopted the role of cooking for males, who were then freed to spend more time hunting. “Relying on cooked food creates opportunities for cooperation, but just as important, it exposes cooks to being exploited”, he writes. “Cooking takes time, so lone cooks cannot easily guard their wares from determined thieves such as hungry males without their own food”. Women needed male protection.
Dr Wrangham cites studies demonstrating that strictly adhering to raw-food diets has difficulty providing adequate energy over time, and notes that in one survey, 50 per cent of the women on a vegan diet stopped menstruating. He refers to studies that suggest that living on an unpredictable raw plant food diet increases the difficulties of surviving when compared to access to unpredictable cooked foods (flesh and plant). Even castaways have needed to cook their food to survive. “I have not been able to find any reports of people living long term on raw wild food”. Thor Heyerdahl, sailing a primitive raft across the Pacific took along a small stove to cook. Alexander Selkirk, the model for Robinson Crusoe, wrote that he built fires and cooked his food.
Dr Wrangham also questions the popular ‘Man-the-Hunter hypothesis’ underpinning human evolution, which argues that eating meat was the primary force shaping human evolution. Meat eating “has had less impact on our bodies than does cooked food”, he writes. “Even vegetarians thrive on cooked diets. We are cooks more than carnivores”. Though there is poor archaeological evidence of humans controlling fire before 800,000 years ago, the changes to the structure of the human face, teeth, brain, and gastrointestinal tract, since Homo erectus 1.6 million years ago, indicate adaptations to regularly cooked meals.
Once these early humans started to eat soft, cooked food, their jaws and teeth were no longer required to munch ceaselessly, and they became smaller and more delicate. That is why we don’t look like apes anymore. Modern humans don’t have significant fangs, our jaw structure is weak and does not articulate like a carnivore, our blunt teeth are not efficient at chewing and our mouths are small. Vegans use these anatomical facts to argue that we are adapted to eat raw foods and not flesh foods. But Dr Wrangham believes these facts and the current anatomy of the human gut, strongly indicate that we are, as he colourfully puts it, “the cooking apes, the creatures of the flame”.
The more cooked food these hunter-gatherers ate, the more their gastrointestinal tract adapted to cooked food and became more compact. As they spent less time eating, they had more free time to explore how to survive with more quality, predictability, tool use and social interaction—around a central campfire focus.
For the last few decades, those of us living with technology have the luxury of predictable access to a surplus of attractive foods, with none of the brutal experiences of actual hunting and gathering nor the rigours of regularly being forced to spend considerable periods of time without food. Most of us also have become rightly concerned about the health effects of industrial chemicals that are being used in the growing, packaging and preservation of food. Most of us desire that food should be as natural as possible, that is ‘organic. We also demand food quality—taste, smell, presentation, texture and adequate volumes to satisfy our indulgence. The fast modern lifestyle, commercial pre-cooked and corporately presented and packaged fast foods are becoming more the norm these days, eliminating the traditions of kitchen cooking and communal eating. Dr Wrangham’s well written book offers a wake-up call to review the human qualities related to cooking in our lives, and the benefits to cook foods well to assist health and wellbeing.