The roots of human diet (Part I)
To help us navigate through a maze of modern diets and figure out which foods can be truly healing, it makes sense to take a look at our history on Earth.
After all, we have been around for a while. Remains from our earliest ancestors have been dated as far back as 4.4 million years and there has been little change in our genetic makeup for the past 300,000 years.
Today we know conclusively that early human ancestors developed primarily as hunters and scavengers of meat, although a variety of nuts, berries and roots also played a role in diet. Tools shaped from rock and used for hunting have been dated back 2.5 million years and we have evidence that 350,000 years ago our human ancestors were using fire for making weapons, cooking food and as a source of warmth and light.
From 1 million to 10,000 years ago the earth was covered by widespread glacial ice. Humans not only survived, they were able to thrive and colonize the entire Old World during this period largely thanks to fire, clothing and their ability to exploit vast quantities of game.
About 10,000 years ago, at the end of the Ice Age, humans began to congregate in larger numbers, eventually creating cities. A need was felt for a steady supply of food for an ever-growing population, and agriculture took hold. However, its introduction was very gradual and took thousands years to spread to the entire human population.
With agriculture and farming came the introduction of entire new food groups previously unknown to the human race, especially cereal grains and dairy products. This is a significant change, because the large quantity of starch contained in grains had never been a part of human diet. For millions of years, humans had either never eaten starch or eaten it only sporadically and in small amounts. Since starch is digested down to sugar it presented a new challenge for human metabolism.
Early on, humans cultivated a variety of grains with broad genetic variability and relatively low starch content. Some of these primitive grains contained gluten, while others contained many different proteins. Consumption of such a variety of grains reduced the risk of intolerance. Early breads such as those described in the Bible were made from a variety of sprouted grains that were both higher in protein and, by today’s standards, very low in starch content.
As bread making evolved and yeast came into use, people started to seek out and develop grains that contained only gluten. This was not for health reasons, but simply because yeast causes gluten to rise and produces a very appealing (and addictive) type of bread.
Dietary change continued to accelerate through the centuries with the development of selective agriculture and the discovery and large-scale production of new foods including sugar, which was first produced industrially two hundred years ago.
Although the societal evolution that accompanied this diet change took us to unprecedented cultural and technological achievements, the cost that we are paying is poor health for many.
(The anthropological data in this section is summarized mainly from the book “Life Without Bread” by C. Allan, PhD and Wolfgang Lutz, MD. Part II of this series on diet will appear in my October newsletter.)
