Laboratoire de Psychologie Cognitive, Aix-Marseille Université, Marseille, France.
Hungry Heart Farm and Dietary Consulting, Conley, GA, USA.
Commun Biol. 2023 Nov 23;6(1):1190. doi: 10.1038/s42003-023-05517-3.
Brain tissue is metabolically expensive. Consequently, the evolution of humans' large brains must have occurred via concomitant shifts in energy expenditure and intake. Proposed mechanisms include dietary shifts such as cooking. Importantly, though, any new food source must have been exploitable by hominids with brains a third the size of modern humans'. Here, we propose the initial metabolic trigger of hominid brain expansion was the consumption of externally fermented foods. We define "external fermentation" as occurring outside the body, as opposed to the internal fermentation in the gut. External fermentation could increase the bioavailability of macro- and micronutrients while reducing digestive energy expenditure and is supported by the relative reduction of the human colon. We discuss the explanatory power of our hypothesis and survey external fermentation practices across human cultures to demonstrate its viability across a range of environments and food sources. We close with suggestions for empirical tests.
脑组织的代谢需求很高。因此，人类大脑的进化必然伴随着能量消耗和摄入的相应变化。提出的机制包括饮食的转变，例如烹饪。然而，重要的是，任何新的食物来源必须能够被大脑只有现代人三分之一大小的原始人类所利用。在这里，我们提出原始人类大脑扩张的最初代谢触发因素是食用外部发酵的食物。我们将“外部发酵”定义为在体外发生，而不是在肠道内发生的内部发酵。外部发酵可以增加宏量和微量营养素的生物利用度，同时减少消化能量消耗，这与人类结肠的相对缩小是一致的。我们讨论了我们假设的解释力，并调查了人类文化中的外部发酵实践，以证明其在各种环境和食物来源下的可行性。最后，我们提出了一些实证检验的建议。
