The book describes a fascinating and also terrifying story of humankind. In the following text, I will share with you the passages that fascinated me as a dietitian.
The genus Homo is the only one in the entire animal kingdom to have come up with massive thinking machines. But what was our price for high intelligence?
The fact is that a jumbo brain is a jumbo drain on the body. It’s not
easy to carry around, especially when encased inside a massive skull.
- It’s even harder to fuel. In Homo sapiens, the brain accounts for about 2–3 % of total body weight.
- The brain consumes 25 % of the body’s energy when the body is at rest.
- Humans diverted energy from biceps to neurons. Their muscles atrophied.
Another characteristic human feature is upright walking. This ability also has significant disadvantages:
- Humankind paid for its lofty vision and industrious hands with backaches and stiff necks.
- Women paid extra for an upright gait. It required narrower hips,
constricting the birth canal – and this just when babies’ heads were
getting bigger and bigger.
And now some information about nutrition: the best thing the fire did for humans, apart from providing protection, was to cooking. Heat treatment of foods opened up a whole new segment of nature’s supermarket to humans.
The advent of cooking enabled humans to eat more kinds of food, to devote less time to eating, and to make do with smaller teeth and shorter
intestines. Humans had a far easier time chewing and digesting old favourites. Some scholars believe there is a direct link between the
advent of cooking, the shortening of the human intestinal track, and the
growth of the human brain. Since long intestines and large brains are
both massive energy consumers, it’s hard to have both.
With the advent of agriculture and industry, “reservations for idiots” were created. The average brain size of Homo sapiens has even decreased since he started farming.
The foragers’ secret of success, which protected them from starvation and malnutrition, was their varied diet. Farmers tend to eat a very limited and unbalanced diet. Especially in premodern times, most of the calories feeding an agricultural population came from a single crop – such as wheat, potatoes or rice – that lacks some of the vitamins, minerals and other nutritional materials humans need.By contrast, ancient foragers regularly ate dozens of different foodstuffs.
Humans are omnivorous apes who thrive on a wide variety of foods. Grains made up only a small fraction of the human diet before the Agricultural Revolution. A diet based on cereals is poor in minerals and vitamins, hard to digest, and really bad for your teeth and gums.
Hunter-gatherers spent their time in more stimulating and varied ways, and were less in danger of starvation and disease. The Agricultural Revolution certainly enlarged the sum total of food at the disposal of humankind, but the extra food did not translate into a better diet or more leisure. Rather, it translated into population explosions and pampered elites. The average farmer worked harder than the average forager, and got a worse diet in return. The Agricultural Revolution was history’s biggest fraud.