What Did Our Ancestors Eat?
By Stanley M. Garn and William R. Leonard
Nutrition Reviews, Vol.47:11 (1989)
Abstract: Over the millennia various hominoids and hominids have subsisted on very different dietaries, depending on climate, hunting proficiency, food-processing technology, and available foods. The Australopithecines were not browsers and fruit-eaters with very high intakes of vitamin C; rather they were scavengers of kills made by other animals. The hominids who followed did include some cold-climate hunters of large game, but the amount of animal protein decreased with the advent of grain-gathering and decreased further with the introduction of cereal agriculture, with a concomitant decrease in body size. From what we know about food adequacy, preparation, and storage, the notion that the postulated “primitive” diet was generally adequate, safe, and prudent can be rejected. Over evolutionary time, many of our ancestors ate poorly, especially during climatic extremes, and they were often at risk for vitamin deficiencies, food-borne diseases, and neurotoxins. Until the advent of modern pro- cessing technologies, dirt, grit, and fiber constituted a large part of most early diets
It is a reasonable notion, consistent with the tenets of evolutionary biology, that the nutritional requirements and dietary needs of contemporary human beings were established in the prehistoric past. It follows that some dietary practices that may be “unhealthy” for contemporary human beings are disadvantageous because we are not adapted to such nutrient excesses or deficiencies. For these reasons we now witness considerable interest in what our ancestors ate and various attempted reconstructions of the beneficial “diets” our ancestors presumably enjoyed. Inferences as to the diets of fossil hominids and fossil hominoids are equally cited by advocates of megavitamin therapy, by those who urge increased consumption of non-digestible fibers, and by advocates of a high-protein dietary regimen.
Some workers in human nutrition see us as the descendants of foraging and brows- ing and fruit-eating ancestors, with a diet necessarily high in ascorbic acid. Thus Tobian wrote, “prehistoric humans and hominids . . . lived as pure hunter-gatherers and ate only the natural food that could be ob- tained from hunting or collecting vegetable materials such as roots, fruits, tubers, nuts, grains, and seeds.” Others working in the field of human nutrition view contemporary mankind as the recent descendants of animal-hunting, flesh-eating ancestors of the ice age, like the classic Neanderthals or the polar Eskimo. In consequence they view a daily intake of 1 g of quality protein/kg of body weight as far too low, even though it sustains life and allows growth. Still others draw attention to the presumed seed-eaters of our most distant past, or grubbers and gatherers still extant, with diets high in insoluble fiber and stool volumes of remarkable size.