Christopher M. Palmer, MD, is a Harvard psychiatrist and researcher working at the interface between metabolism and mental health. He is the director of the Department of Postgraduate and Continuing Education at McLean Hospital and an assistant professor of psychiatry at Harvard Medical School. For more than two decades, he has held leadership roles in psychiatric education at Harvard, McLean Hospital, and nationally. He spent more than 15 years conducting neuroscience research in the areas of substance use and sleep disorders. On top of these academic pursuits, he has continued to practice psychiatry, working with people who have treatment-resistant mental disorders using a variety of standard treatments. He has been pioneering the use of the medical ketogenic diet in the treatment of psychiatric disorders—conducting research in this area, treating patients, publishing academic articles, and speaking globally on this topic. Most recently, he has developed the first comprehensive theory of what causes mental illness, integrating biological, psychological, and social research into one unifying theory—the brain energy theory of mental illness.