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Psychiatrist says most in field deny diet plays role in mental illness

On Purpose with Jay Shetty · Harvard Psychiatrist REVEALS We Have Been Treating Mental Illness All WRONG · July 3, 2026
Psychiatrist says most in field deny diet plays role in mental illness
On Purpose with Jay Shetty
On Purpose with Jay Shetty
Harvard Psychiatrist REVEALS We Have Been Treating Mental Illness All WRONG
"If you talk to most psychiatrists or neuroscientists and ask them, does diet play a role in mental health? Most of them will say probably not, that the brain is just a really complicated organ and there's no way that what we eat, nutrition, would play a role in something like ADHD or even depression, and certainly not something like bipolar disorder or schizophrenia."
Dr. Chris Palmer, a Harvard psychiatrist, told a Senate roundtable that most psychiatrists dismiss the role of diet in mental illness, despite mounting evidence linking metabolic dysfunction to conditions like schizophrenia and bipolar disorder. He argues this blind spot is leaving patients without effective treatments and that nutrition is foundational to brain health.

About this episode

Harvard psychiatrist Dr. Chris Palmer appeared on On Purpose with Jay Shetty to argue that the American mental health crisis is fundamentally a metabolic disorder caused largely by diet, a position that challenges mainstream psychiatry. Palmer, who recently addressed the Senate on the chronic disease epidemic, revealed that the FDA allows food manufacturers to self-certify new chemical additives as safe without rigorous testing, citing a recent case where Tara flour hospitalized over 400 people with liver failure. He stated that most psychiatrists deny diet plays any role in conditions like schizophrenia or bipolar disorder, despite mounting evidence linking metabolic dysfunction to mental illness. Palmer disclosed that only 7% of American adults are metabolically healthy by standard biomarkers, and that 93% have at least one metabolic abnormality. He presented evidence that aspartame, found in over 500 diet products, causes anxiety in mice that persists for two generations even when offspring are never exposed, suggesting epigenetic changes. Most controversially, Palmer reported that thousands of people with severe mental illnesses including schizophrenia and bipolar disorder are achieving full remission using ketogenic diets, sometimes eliminating psychiatric medications entirely. Twenty controlled trials are now underway worldwide testing ketogenic diets for mental health conditions, with over 1,900 participants already enrolled in published studies. Palmer noted the ketogenic diet was developed 100 years ago as an evidence-based epilepsy treatment. He shared that his mother developed a treatment-resistant psychotic disorder that destroyed her life and left their family homeless, motivating his career-long search for better interventions. Palmer emphasized that while psychiatric medications sometimes work, far too many patients don't respond and are told they have incurable chronic disorders. He expressed hope that within 10 to 20 years, the mental health field will undergo a transformation and view current treatment approaches as nearly barbaric.

Key takeaways

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