What does human biology actually tell us about the way we are designed to eat, metabolise energy and adapt to our environment? In this episode of The Integrative Continuum, I am joined by Kaya Genc, an interdisciplinary research scientist and cofounder of the Evolutionary Frameworks Project. Kaya's work brings together evolutionary biology, systems physiology, mathematical modelling, metabolic neuroscience and research methodology in an attempt to understand human biology through a much wider lens than nutrition science alone. This became a fascinating and wide ranging conversation. We explore the limitations of nutritional epidemiology and why association should not automatically be interpreted as causation. We discuss confounding variables, relative versus absolute risk, research methodology and the importance of questioning how conclusions are reached rather than simply accepting headlines. From there, we move deeply into human evolution and nutrition. Kaya explains the reasoning behind his view that humans display many characteristics consistent with a high trophic level, facultative carnivorous physiology, while also possessing adaptations that allow us to utilise starch and other foods when necessary. We discuss gastric acidity, digestive anatomy, evolutionary changes in the gut, amylase adaptation, stable isotope evidence, brain development, fatty acids, protein, animal foods and the continuing debate around what constitutes a species appropriate human diet. The conversation also explores plant defence compounds, fibre, gut health, fructose and uric acid, glucose metabolism, the Randle cycle, cholesterol, LDL, triglycerides and the ongoing debate surrounding cardiovascular risk. We also discuss nutrient density, organ meats, seafood, fasting, animal based nutrition and the difference between simply surviving on a diet and potentially functioning optimally on it. Later in the conversation we move into pharmaceuticals, symptom suppression versus addressing underlying mechanisms, GLP 1 medications, statins, proton pump inhibitors and the importance of understanding what medications are actually doing within a biological system. Kaya also shares his personal experience with epilepsy, anticonvulsant medication and brain surgery, and how those experiences helped shape his interest in physiology, neuroscience and research. Perhaps the most important theme running throughout this conversation is not that anyone has all the answers. It is that science should remain open to questioning. Good science requires us to distinguish between what has been demonstrated, what is strongly supported, what remains theoretical and what may eventually need to be revised as new evidence emerges. As Kaya says during the conversation, he is trying to understand the best current evidence available while remaining willing to change his position if better evidence appears. That philosophy sits very closely with the purpose of The Integrative Continuum: Standing by the truth as I know it and as I learn it. Topics discussed include nutrition research, epidemiology, human evolution, carnivore and ketogenic diets, plant based nutrition, protein, fat, carbohydrates, fibre, fructose, cholesterol, LDL, metabolic health, fasting, gut physiology, nutrient density, pharmaceuticals, GLP 1 medications, evolutionary biology, neuroscience and scientific methodology. This is a long form conversation intended to encourage questions, discussion and further investigation rather than provide a single final answer.
