The question I will address in this seminar is “Why is it that our species, with unprecedented privilege in terms of science and technology, so commonly fails in something as fundamental as eating a healthy diet, whereas other species succeed using raw biology alone?” In this seminar I will use examples from my own research examining the mechanisms of diet selection in non-human animals, both in the lab and the wild. This work shows that the key to healthy eating in species as diverse as insects to apes is nutrient specific appetites which interact to ensure that the diet is sufficient and balanced with respect to current requirements. I then demonstrate how understanding the dynamics of nutrient specific appetites has led to a new theory of human obesity, the Protein Leverage Hypothesis, and present research testing this hypothesis. Results suggest that humans too have nutrient-specific appetites and, paradoxically, the appetite for protein, not fats and carbohydrates, is most closely associated with energy over-consumption and obesity.
