Physician and molecular geneticist Michael Nehls, MD, PhD joins the show to make the case that trace-dose lithium may function as an essential nutrient with meaningful implications for brain health—especially for the hippocampus, which he describes as a key hub for cognitive resilience. Nehls walks through the science and his interpretation of why this idea has remained outside mainstream medicine, pointing to historic regulatory decisions (including a 1949 FDA ban on certain lithium uses) and decades of stigma tied to high-dose psychiatric treatment. He also raises concerns about institutional and industry incentives that, in his view, discourage broader recognition and research into lithium’s potential role at nutritional levels.