Is Bipolar Disorder Really a Diet Problem?

Ian’s personal discovery and the growing body of case reports and pilot data position the ketogenic diet as a promising metabolic therapy for bipolar. Unlike pharmaceuticals that often worsen metabolic health, the diet improves insulin sensitivity, body weight, and cardiometabolic markers. The Edinburgh pilot study demonstrated significant reductions in brain glutamate (11–13%) and blood lactate, both objective markers of brain energy metabolism. Patient advocacy groups and philanthropists like the Baszucki family have funded early research, and large randomized controlled trials are now being launched. The protocol is not yet standard care, but the metabolic psychiatry hub is building evidence. Clinically, it is positioned as an adjunct or, in some cases, an alternative to medication pending further research.

Ian highlights the importance of not trivializing medication withdrawal. While he eventually stopped medications, he describes it as a long journey that required family support and professional guidance. He notes that many medications for bipolar, like antipsychotics, directly cause metabolic dysfunction (weight gain, diabetes), ironically worsening the very insulin resistance that may underlie the illness. This creates a complex risk-benefit calculus: acute stabilization may necessitate drugs, but long-term metabolic harm may necessitate dietary interventions that can eventually allow dose reduction. The protocol emphasizes that metabolic therapy may reduce the need for medication, but the transition must be managed cautiously, ideally within a clinical trial or integrated care model.

Mark Hyman describes building his functional medicine practice by ordering tests that traditional doctors ignore, then backfilling his observations with scientific literature. He found that when he corrected these underlying imbalances—through diet, supplements, detoxification, and microbiome repair—patients’ psychiatric symptoms often resolved, even though that was not his primary goal. This protocol is now moving into academia, with metabolomics studies at Edinburgh and the Metabolic Psychiatry Hub aiming to identify blood-based signatures of bipolar. The panel bridges the gap between self-experimentation and evidence-based care. Hyman’s company, Function Health, democratizes access to many of these biomarkers with over 110 tests and affordable pricing.

Ian mentions that when he read Mark Hyman’s Ultramind Solution, he meticulously went through the list of supplements—CoQ10, carnitine, and others—and tried them one by one in a spreadsheet. Although he later found that the ketogenic diet was the most powerful intervention, these supplements formed part of his early self-experimentation. Hyman emphasizes that these are part of a functional medicine approach that targets root causes. While not a substitute for diet, they can shore up metabolic pathways while deeper dietary changes take effect.

Ian’s pivotal insight came when he started correlating his mental state with blood ketone numbers. He realized that the days he felt well were the days his ketones were elevated. This shifted his approach from a generic weight-loss diet to a targeted metabolic therapy. The protocol empowers patients to self-experiment within safe bounds, providing an objective measure that is often missing in psychiatric treatment. Combined with clinical oversight, ketone monitoring can help tailor diet composition and timing.

Ian’s team used MRS in their pilot study and found that glutamate reductions were larger and faster than with standard mood stabilizers. This provides neurochemical validation for the ketogenic diet. Mark Hyman notes that psychiatrists rarely order brain imaging, but these metabolic imaging tools could revolutionize how we diagnose and monitor mental illness. The research is scaling up in the larger randomized controlled trial, which will add rigor and perhaps lead to clinical adoption. For now, it remains a research tool, but it demonstrates that we can objectively measure the brain’s metabolic health.

Ian and Mark both advocate that insulin resistance should be a standard vital sign in psychiatry. Large epidemiological studies show that early-life insulin resistance predicts later psychiatric diagnoses and more severe progression. Despite this, less than 1% of tests measure insulin. Hyman’s Function Health now offers the c-peptide/insulin ratio, a highly specific test that matches the research gold standard. The protocol is simple: if a patient is insulin resistant, dietary and lifestyle interventions (low-carb, keto, exercise) become priority treatments, potentially reducing the need for medications that worsen metabolic health.

Ian Campbell argues that bipolar is fundamentally an energy disorder, where mitochondria in the brain cannot produce enough ATP efficiently. This manifests as severe depressive states (energy deprivation so extreme it feels like being deprived of oxygen) and manic/hypomanic states (bursts of uncontrolled energy). He draws an analogy to a car engine: addressing neurotransmitters is like adjusting the air conditioning while the engine is on fire. The metabolic view suggests that fixing the engine—mitochondrial function and insulin signaling—can resolve downstream neurotransmitter problems without directly targeting them. This idea is supported by early 20th-century observations, patient phenomenology, and emerging metabolomic and imaging data. The shift is gaining traction in mainstream research, with Cambridge and Edinburgh now running dedicated programs.

Ian stumbled onto a low-carbohydrate diet while trying to lose weight and noticed his thinking became clear and his mood stabilized. He then started measuring blood ketones and correlated higher ketone levels with periods of remission. This aligns with the metabolic theory: ketones provide an alternative, more efficient fuel for the brain, bypassing the impaired glucose metabolism seen in insulin-resistant brains. In epilepsy, ketosis reduces glutamate-driven excitotoxicity and stabilizes neural networks. The same mechanism may apply in bipolar, calming the hyperexcitability of mania and restoring energy homeostasis in depression. A pilot study at Edinburgh showed an 11–13% reduction in brain glutamate after 6–8 weeks on a ketogenic diet, larger than the ~6% reduction seen with lamotrigine over a longer period. This suggests the diet may act through the same anti-glutamatergic pathways as existing medications, but more potently and with fewer metabolic side effects. Funding from the Baszucki family, whose son Matt experienced remission after years of treatment-resistant bipolar, has been pivotal in jumpstarting this research.

Ian's research posits that bipolar disorder is a form of metabolic plasticity gone awry. In nature, many animals seasonally shift between glucose and fat/ketone metabolism—hibernating bears suppress insulin signaling and live off fat, while migratory birds become hypermetabolic at the spring equinox. Humans conserved the same circadian and metabolic regulatory pathways (clock genes, mTOR, AMPK, AKT, sirtuins). In the modern world, constant artificial light, processed carbohydrates, and lack of seasonal food variation keep these systems perpetually disrupted. Bipolar patients may be especially sensitive to photoperiod changes, with mania spiking at the spring and autumn equinoxes and depression at the winter solstice. This seasonal energy modulation, once advantageous for survival, now manifests as illness. The hypothesis explains why ketogenic diets, which mimic winter metabolism (fat-burning, ketosis), can stabilize mood—they realign the body's expected metabolic state with its actual fuel source, calming the seasonally driven energy swings.

Ian highlights that insulin signaling pathways (PI cycle, GSK3, AKT, mTOR) are the same pathways targeted by lithium, the gold-standard bipolar drug. But lithium's effects are blunt and can cause long-term metabolic damage. Rather than using drugs that further disrupt metabolism, directly measuring and treating insulin resistance with diet could address the root cause. Mark Hyman notes that less than 1% of diagnostic tests in the U.S. measure insulin, yet insulin resistance underlies a vast proportion of chronic disease, including mental illness. New tests like Quest's c-peptide/insulin ratio provide a precise measure of cellular insulin resistance. Function Health, co-founded by Hyman, now offers these tests widely. The implication is that every psychiatric patient should have metabolic health markers checked as part of their standard workup, and interventions like low-carb or ketogenic diets, exercise, and supplements could improve both mental and physical outcomes.

The Edinburgh pilot study tracked lactate as a metabolic biomarker and found significant reductions in blood lactate on a ketogenic diet, parallel to symptom improvement. Ian compares the sensation of bipolar depression to the lactic acid burn and exhaustion of running a marathon—except paused indefinitely. Elevated lactate in the brain contributes to the feeling of physiological crisis. By switching the brain's fuel from glucose to ketones, the diet restores mitochondrial efficiency, reducing lactate production. This provides a measurable, mechanism-based marker that could eventually guide clinical decisions, much like HbA1c for diabetes. The resurgence of lactate as a research endpoint signals a shift toward objective metabolic monitoring in psychiatry, potentially allowing personalized dosing of dietary interventions.