How Agriculture Changed Our Diet
Fossil evidence reveals that (about 10-15,000 years ago) environmental pressures obliged humans to change their eating habits. These pressures included the extinction of large mammals, the depletion of easily tracked game and the rise in population density. As a result, humans began to change their eating habits and moved from a largely animal-based diet to a more plant-based diet.
More Carbs, Less Meat
The agricultural revolution had a huge impact on hunter-gatherer dietary habits. For the first time in their evolutionary history, humans began consuming significant amounts of carbohydrate-rich foods, such as whole grain cereals (eg. barley, oats, corn, wheat, rye, and rice). Other agricultural foods such as legumes (beans) starchy roots and tubers, fruits and berries also added to the growing carbohydrate intake. This dietary change is easily proven by two facts: (1) cereal grains cannot be digested by the human gastrointestinal tract without a significant degree of grinding and cooking over open fires. (2) Milling stones first appeared in the area of the Middle East about 10-15,000 years ago.
The Spread of Cultivated Plant Food
Wheat was first sown and harvested in the Middle East about 10-15,000 years ago and slowly spread to Europe. Rice became established about 7,000 years ago in India and China, while maize or corn was domesticated in Central America about 7,000 years ago.
But Carbohydrate Foods Were Healthier
Although the cultivation of high-carb food triggered revolutionary changes in hunter-gatherer eating habits and digestion, these early plant foods were almost exclusively whole grain. Meaning, the preparation and cooking processes left intact most of the natural grain (eg. bran). As a result, the carbohydrate in these foods was digested and absorbed slowly, so their effect on human blood glucose was gradual and relatively small. This contrasts strongly with the high-glycemic carbs of today’s modern diet and their negative effects on our blood sugar levels. See Guide to GI
Exercise Was a Universal Habit Among Hunter Gatherers
Another crucial difference, when comparing the diet health of today with that of earlier human life, is the issue of physical activity. In the Stone Age era, and for a long time afterwards, physical exercise was essential to survival. Daily processes such as hunting, drawing water and collecting firewood burned large amounts of calories, and helped to develop significant muscular and bone strength. When assessing the diet-related health of earlier humans, the contribution of physical fitness to the health and longevity of hunter gatherer and later generations should not be underestimated.