Detoxifying/Removing Antinutrients

Like many other primates, humans face numerous anti-nutrient compounds in many of the plant foods, which constitute a substantial part of their diet. The two major classes of anti-nutrients are A) toxins such as alkaloids, saponins and various glycosides, and B) digestibility reducing substances such as, tannins, lectins and lignins. Non-human hominids consume only raw plant matter. All hominids are known to practice geophagy of various clays as a behavioral adaptation for treating ingested antinutrients. Chimpanzees also reingest passed seeds as a possible way of detoxifying these. Raw plant matter is part of the diet of most human populations, however, the majority of human plant diet is processed by cooking, leaching, fermenting, or even sprouting prior to consumption. These treatments have massively expanded the possible range of plant food resources for humans, including many additional tubers, and seeds, which would be too toxic or indigestible for any non-human hominid. In addition, humans have much reduced the content of antinutrients (while augmenting desired components such as starch) in most domesticated crop plants by selective breeding. Some crops are grown chiefly for their antinutrients such as coffee, tea, and tobacco, but these have little or no nutritional value. The capacity of non-human hominids to partially digest cellulose and hemicellulose, which could also be considered antinutrients, remains poorly understood but is likely to involve specialized gut microbiota including organisms such as Troglodytella spec. described in gorillas and chimpanzees.