Food for Thought: Nutrition & Diet
Over the last 10 years, the fascination for identifying the ‘Natural Human Diet’ has expanded beyond anything imagined by Eaton and Konner who authored the first paper on Paleolithic Nutrition. The publication of Paleodiet and Paleonutrition cookbooks has exploded, almost exponentially although the science underlying these diets is not always very convincing. Over the same period, we have seen another explosion in the scientific literature on the diets of some fossil members of our lineage based on dental microwear analyses, stable isotope analyses, and microfossils and DNA in dental calculus. Around 2 million years ago some of our fossil relatives consumed diets unlike anything observed in living primates (e.g., sedges), others began to eat meat, and still others maintained the more general primate diet of leafy plants, fruits, seeds, nuts, and insects. Based on our knowledge of the diets of living nonhuman primates, of extant non-agriculturist humans, and of prehistoric humans, we know that living humans can eat virtually everything and that what cannot be eaten, we often feed to animals that we subsequently consume or we co-opt these animals to provide us with blood or milk for consumption. Yet, these sources show that the highly processed and heavily starch-based diet ingested most commonly across living humans today has existed for only 15,000 years at the very most. The extraordinary dietary flexibility of humans must be considered in order to understand the evolution and appearance of our species, Homo sapiens.