Deadly Harvest: The Intimate Relationship Between Our Heath and Our Food (6 page)

The gorilla is what is known as a vegan, a creature that consumes no food of animal origin whatever. A male gorilla is a gentle giant weighing 450 pounds of solid bone and muscle. He can climb trees with ease and swing his great weight through the branches. Even so, to keep his body supplied, he needs to eat 50 pounds of vegetation per day. His diet is chiefly leaves, fruit, and even small twigs and bark. He can spend up to eight hours eating. Vegetation is not rich in calories, so the gorilla has to economize energy expenditure—he is a slow, deliberate mover.

Chimpanzees are rather smaller than the average human and they are much more active than the gorilla. They, too, have a diet that is focused on plant food, but more oriented to ripe fruit and young leaves. In addition, they kill and eat small creatures, particularly monkeys and small wild pigs. Some chimpanzees even poke a stick into a termite nest and eat the termites that crawl out. It is estimated that around 6% of the chimpanzee’s calories are of animal origin.

Humans, gorillas, and chimpanzees share an ancestral line that goes back to fruit-eating creatures. Over the millennia, their eating pattern has diverged somewhat, but the same digestive system is pressed into service. All humanlike creatures share the same basic pattern. As anthropologist Katherine Milton observes, they have a simple stomach, a lengthy small intestine, a modest-sized cecum, and a corrugated colon.
³⁵

The cecum is the first region of the colon. It has a deep layer of muscle that kneads the contents and propels them forward. In contrast to the human cecum, the
carnivore
cecum is much smaller. There are other differences too: in the cat and dog, muscle contractions of the cecum are much more vigorous and they can reverse direction, sending the contents back up into the intestine.

Humanlike creatures also have an appendix. This is an unusual structure and contrary to popular belief, it serves a useful purpose. It secretes digestive helpers such as mucin, eripsin, and amylase; the appendix is also a powerful producer of antibodies for the immune system. The only other type of creature that has an appendix is leaf-eating animals (folivores), notably the rabbit and the capybara (a large, vegetarian, South American, semi-aquatic creature related to the guinea pig).

Surprisingly, it is difficult to be precise about the true dimensions of a digestive system. The various components are particularly elastic and the proportions can vary significantly from one individual to another. According to an individual’s eating habits, the stomach is contracted or bloated; the colon longer or shorter. Indeed, a baby’s colon has proportions similar to those of other apes. As humans mature, their colon, relatively speaking, shortens.
³⁶
But this may only happen to Westerners on a low-fiber diet. It is suggestive that in other apes, the opposite happens—their colons get longer with age. It would be surprising if ours were not intended to do the same. Gorillas have long colons anyway compared to humans. This is where they digest their large intake of plant material.

However, we can learn even more from the curious fact that our digestive system is even closer in design to that of the capuchin monkey. Capuchins are little, stocky, nimble creatures that live in Central America. Like humans, capuchins have a small intestine that is lengthy compared to the colon. The overall length of gut (small intestine plus colon) compared to body size is also small compared to other apes and monkeys. This indicates that humans are designed for a similar
type
of food supply. Capuchins eat a high-quality diet made up of unusually rich wild foods, both fruits and oil-rich nuts. They also spend a disproportionate amount of time seeking out animal matter, including grubs, grasshoppers, and small animals.

Similarly, savanna baboons painstakingly seek out small nutritious food items—up to 3,000 in a day, including gums, flowers, fruits, and small animals and insects. Neither the baboon nor the capuchin monkey is as close to us genetically as the great apes. However, they have feeding environments that are more similar to the human one and they evolved digestive systems that have a similar design to ours.

What Kinds of Foods are Our Bodies Designed to Capture?

Just like the gorilla and chimpanzee, our jaws and molars are designed for chewing and grinding. Like the great apes, we have front teeth in the shape of a chisel—good for taking a bite out of an apple. As we saw earlier, we have back teeth made for grinding. Unlike carnivores, our jaws can move from side to side for better chewing. Our teeth are closely spaced, unlike those of a carnivore, who has needle-shaped teeth with wide gaps. Our saliva contains the enzyme ptyalin, which powerfully pre-digests plant carbohydrate.

Chimpanzees and baboons use their hands a great deal to prepare their food. It is no coincidence that the same hand, with its ability to grasp an object, is also one that is good for grasping a branch. Like us, these creatures show great dexterity: they will pick out the choice part of a plant or unwrap a leaf to find a grub inside.

LIVING THE WAY NATURE INTENDED

In this chapter, we have set the scene, noting many facts and describing the remarkable advances in knowledge about our human origins. It is a story that could not have been written even ten years ago. We can now properly understand how human beings are a part of nature—it is liberating to know how to live the way nature intended.

We have built up a picture of the lifestyle experienced by our ancestors for hundreds of thousands of years. We have identified the kinds of feeding opportunities they had and described the use that they made of their environment, including their behavior within it. We know that even today, our digestive systems, biochemistry, brains, psychology, and bodies are still those designed for life in the savanna of East Africa. I call this lifestyle the “Savanna Model.”

We have not yet done any interpreting or drawn any conclusions, which will come later as we piece together yet more evidence. However, already we can discern the major outlines of our Owner’s Manual. Our African Pleistocene ancestors had a food supply in which plant material was a major component and animal matter was a moderate component. We have seen that the
types
of plants and animal matter were quite different from what we consume today. We will discover that these differences are of capital importance. Their diet contained certain types of fat but not others. What they did
not
eat is of equal importance: we eat many groups of food today that did not form part of our ancestral diet.

Contrary to modern myth, those far-off ancestors lived long, healthy lives. In so many fundamental ways, our modern lives have diverged from the lifestyle that Nature intended. It is estimated that the average Westerner loses 10 to 15 years of life thanks to dysfunctional eating habits. Furthermore, those extra years would be lived in great physical shape to the end.

This ancestral lifestyle seems exotic—far removed from how we live today—and few would like to return to it. Indeed, population densities are now so high that there just is not enough space to go around. So, we are stuck with what we have got; there is no going back. However, the good news is that we can work intelligently to get the best of both worlds, ancient and modern.

In the next chapter, we look at the distortions that have occurred in human dietary patterns worldwide since that far-off time. We will see what impact these distortions have on our health and well-being, and we will use these insights to write more segments of the Owner’s Manual.

Chapter 2

The Farming Revolution and Its Consequences

In the last chapter, we explored the lifestyle of our ancient ancestors in our East African homeland and dubbed it the “Savanna Model.” Remarkably, our bodies have not changed significantly since then and, ideally, we would still live and feed ourselves the same way, even today. However, as history will show, things changed. We will now continue our human story by exploring how and why human lifestyles drifted away from this ideal.

Just before the dawn of recorded history, so-called advancements took place that set most of humanity on a path that led firmly away from our naturally adapted lifestyle. This process repeated itself throughout the world. As we will see, most humans were no longer nourishing their bodies to the best advantage.

This chapter puts the spotlight on the major departures from the ideal diet, departures which happened, for the most part, quite unwittingly. As the centuries rolled by, new techniques and new foods came along that led us ever further from our ancestral feeding patterns. From the 19th century, it became obvious that our food supply was not always nourishing populations properly. It also became apparent that the food supply was increasingly vulnerable to dubious practices. We review how government agencies tried to correct both these matters and why we cannot rely on them to protect the public interest. This will give us a perspective on how we ended up with the food supply that we have.

THE MAJOR UPSET IN HUMAN NUTRITION

By about 11,000 years ago, the human race had occupied the majority of the world’s land and there was nowhere else to go. The wandering bands of foragers still needed 100 to 200 square miles for each group of 50 people. Nevertheless, as their numbers were still multiplying, these groups came into conflict with one another over territory. More and more they would fight each other with increasing ferocity to protect their living space. The archeological evidence is clear: there are traces of Stone Age battlegrounds from Australia to Europe.

Then, a group of foragers stumbled on a solution to the problem. They discovered how to feed themselves on a much smaller area of land. Instead of wandering their territory in search of their next meal, they took control of their food supply. They had figured out a way to survive on 4 square miles instead of 200 square miles. This was a huge innovation for the human race: for the first time, humans stayed in one place and planted. It would not only change the social behavior of these bands forever, it would also cause a dramatic shift in the human diet, not always with positive results.

The place where it all started was the grasslands of what is now Kurdistan in northern Iraq. Historians call this lifestyle upheaval the “Farming Revolution.” It was important enough to mark the end of the Paleolithic Age and the beginning of the “Neolithic” or New Stone Age. The start of agriculture marked the beginning of this period. It would take man’s use of metals several thousand years later to create the next important period—the Bronze Age. However, for us, it is this agricultural revolution that still influences our life and health today.

The New Stone Age ushered in unforeseen consequences. Because those pioneer farmers were not able to cultivate their usual diet of foraged plants, they found themselves compelled to grow those items that it was possible to grow. For this reason, completely new food groups entered the diet. For the first time in the history of the human race, people started to eat grass seeds. Put plainly like that, it sounds faintly ridiculous, but today we eat grass seeds on a huge scale. Of course, we know them by another name: grains. Those first farmers took the grasses that surrounded their living space and learned to plant, grow, harvest, winnow, and mill
their seeds. These grasses were the ancestors of today’s wheat and barley. This dietary change marked a massive upheaval in human nutrition. It was the first step—but a major one—away from our ancestral diet. We are only now beginning to understand the severity of the consequences.

About the same time, the first farmers also discovered how to grow lentils and garbanzo beans (chickpeas). In this way, 11,000 years ago, and for the first time, we humans started to consume two completely new food categories: grains and legumes. It was the first demonstration that humans could harness nature. However, as we shall see, nature can play tricks on us. Just because we can consume something without an immediate negative reaction, it does not always mean that we should consume it. Indeed, humans can train themselves to eat almost anything. It is one of the lessons that we shall learn: contrary to what most of us fondly imagine, we cannot trust our instincts to tell us what to eat.

Cereal and Legume Defined

Cereal
is just another word for grain. They are all varieties of grasses.
Legume
, also known as “pulse,” is the collective term for lentils, chickpea (garbanzo) beans, peas, soybeans, peanuts, and similar seeds. Some authorities, such as the United States Department of Agriculture (USDA), use the term
dry beans
. They are part of a very large family called Fabaceae, the pea family.

A TECHNOLOGICAL REVOLUTION AND A SHIFT IN SOCIETY

The implementation of basic farming skills meant that other inventions had to follow. Farmers had to devise baskets, fences, hoes, and sickles; they had to build storage silos and houses. Humans found themselves on an exciting, yet demanding, treadmill of creation, manufacture, and construction.