Shebani Sethi and colleagues at Stanford University published this pilot trial in Psychiatry Research in 2024. They enrolled 23 individuals - 5 with schizophrenia and 18 with bipolar disorder - all of whom had existing metabolic problems such as obesity, high blood sugar, or abnormal cholesterol levels. Participants followed a ketogenic diet for 4 months while continuing their regular psychiatric medications.

Among participants who adhered to the diet (verified through blood ketone monitoring), improvements were seen in psychiatric symptom scores, body weight, BMI, waist circumference, blood sugar, and self-reported life satisfaction and sleep quality. The metabolic improvements were particularly notable because people taking antipsychotic medications commonly develop metabolic syndrome as a side effect.

This study is important because it was the first prospective trial specifically designed to test the ketogenic diet in people with serious mental illness. While the sample was small and there was no control group, the positive results across both psychiatric and metabolic outcomes provided the basis for larger randomized trials now underway.

A comprehensive review published in Frontiers in Psychiatry in 2025 examined the evidence for ketogenic therapy in schizophrenia, covering proposed mechanisms, clinical evidence, and future directions. The review synthesized findings from neuroscience, immunology, and clinical psychiatry.

The review highlighted that schizophrenia is increasingly understood as involving neuroinflammation - chronic low-grade inflammation in the brain. The ketogenic diet has been shown to reduce this inflammation by lowering pro-inflammatory cytokines (signaling molecules that drive inflammation), specifically IL-1beta, IL-6, and TNF-alpha. It also shifts microglia (the brain''s immune cells) from an inflammatory state to a protective state.

Additionally, the ketogenic diet addresses mitochondrial dysfunction - another feature of schizophrenia. Brain cells of people with schizophrenia show impaired energy production from glucose. Ketones provide an alternative fuel source that bypasses this dysfunction, potentially restoring normal brain energy metabolism. This "metabolic rescue" hypothesis is one of the most compelling theoretical reasons to test ketogenic diets in schizophrenia.

A case report published in Frontiers in Psychiatry in 2025 documented a male patient with a schizophrenia diagnosis who adopted a carnivore ketogenic diet (consisting entirely of animal products) with support from a nutritional therapy practitioner.

After 9 months on the diet, the patient''s mental health treatment team assessed his schizophrenia as being in clinical remission. He experienced no psychotic episodes during the entire period. His psychiatric medication doses were also reduced during this time, though the report notes that medication changes were made by his psychiatrist and the diet was used alongside, not instead of, conventional treatment.

As the authors acknowledged, this is a single case report - the weakest form of clinical evidence. Individual cases cannot establish causation because many factors change simultaneously. However, the dramatic improvement reported adds to a growing collection of case reports suggesting that some individuals with schizophrenia may respond favorably to ketogenic dietary interventions.

Palmer and colleagues published this review in the Journal of Clinical Medicine in 2022, examining the role of ketogenic metabolic therapy on brain function in serious mental illness. The review integrated evidence from neuroscience, metabolic research, and clinical psychiatry.

The review found that the ketogenic diet enhances the production of GABA (gamma-aminobutyric acid) - the brain''s main calming neurotransmitter - and modulates glutamate metabolism. In schizophrenia, the balance between GABA (inhibitory) and glutamate (excitatory) is disrupted, contributing to psychotic symptoms. By shifting this balance toward more GABA and less excessive glutamate activity, the ketogenic diet may address one of the core neurochemical abnormalities in schizophrenia.

Current antipsychotic medications primarily work by blocking dopamine receptors, which is effective for some symptoms but often leaves others (like cognitive impairment and negative symptoms) poorly treated. A dietary intervention that targets GABA and glutamate could potentially address symptoms that current drugs miss.

Kraft and Westman published a review of clinical implications in Current Opinion in Psychiatry in 2019, tracing the history of ketogenic diet use in psychiatric disorders. They noted that the idea is not new - early reports date back to the 1960s when clinicians observed symptom improvement in hospitalized schizophrenia patients placed on low-carbohydrate diets.

A historical case series described 10 women with schizophrenia who showed improvement in symptoms when placed on a ketogenic diet. While this early work was not conducted with modern research standards, it provides historical precedent for the concept. Modern case reports have continued to document improvements, including cases where patients with treatment-resistant schizophrenia showed meaningful symptom reduction after adopting a ketogenic diet.

The authors argued that the convergence of historical observations, modern case reports, and growing understanding of the metabolic underpinnings of schizophrenia creates a compelling case for formal clinical trials. They called the ketogenic diet a "low-risk, potentially high-reward" intervention worth testing rigorously.

A review published in PMC in 2024 examined the potential dual benefit of ketogenic diets in schizophrenia: addressing both psychiatric symptoms and the metabolic side effects of antipsychotic medications. This "two birds with one stone" approach is considered particularly promising.

Antipsychotic medications, especially second-generation drugs like olanzapine and clozapine, cause significant metabolic problems in up to 60% of patients. These include weight gain (often 10-20 kg in the first year), insulin resistance, type 2 diabetes, high triglycerides, and metabolic syndrome. These metabolic effects contribute to the 15-20 year reduced life expectancy seen in people with schizophrenia.

The ketogenic diet directly addresses these metabolic complications through carbohydrate restriction and improved insulin sensitivity. If it also improves psychiatric symptoms, it could simultaneously treat the disease and its treatment side effects - something no current psychiatric medication can do.

Norwitz and colleagues published this review in Frontiers in Psychiatry in 2024, examining the relationship between sleep, mood disorders, and the ketogenic diet in the context of schizophrenia and bipolar disorder. Sleep disruption is both a symptom and a contributing cause of psychotic episodes.

The review found that the ketogenic diet may improve sleep quality through multiple pathways: reducing brain inflammation that disrupts sleep circuits, stabilizing blood sugar levels (which prevents nighttime awakening from blood sugar drops), and modulating adenosine - a brain chemical that promotes sleep and is influenced by ketone metabolism.

Improving sleep in schizophrenia is clinically important because sleep deprivation can trigger psychotic episodes and worsen existing symptoms. If the ketogenic diet improves sleep as a secondary benefit alongside its metabolic and anti-inflammatory effects, it could create a positive feedback loop of improving symptoms.

A retrospective case series published in Frontiers in Psychiatry in 2025 documented the outcomes of multiple patients with schizoaffective disorder (a condition combining features of schizophrenia and mood disorders) who adopted ketogenic metabolic therapy alongside their regular psychiatric medications.

The case series reported sustained remission of psychotic symptoms and recovery of stable mood in the documented patients. The improvements were maintained over follow-up periods, and some patients were able to reduce their medication doses under psychiatric supervision.

While a retrospective case series cannot prove causation, documenting consistent positive outcomes across multiple patients with a diagnosis that is notoriously difficult to treat adds weight to the hypothesis. The authors called for larger prospective studies to confirm whether the patterns they observed would hold up under controlled conditions.

A case report published in Nutrition and Metabolism described a patient with both schizoaffective disorder and gluten sensitivity. The patient had experienced persistent psychotic symptoms despite multiple medication trials. After adopting a ketogenic diet, which is naturally gluten-free due to the elimination of grain-based carbohydrates, the patient experienced significant improvements in both psychotic symptoms and body weight.

The case illustrates a potential subgroup of schizophrenia patients who may be particularly responsive to dietary intervention - those with co-existing food sensitivities or metabolic abnormalities. Gluten sensitivity has been reported at higher rates in schizophrenia patients compared to the general population, and some researchers have hypothesized that gluten-derived peptides may affect brain function in susceptible individuals.

While this is a single case and cannot establish a general treatment principle, it suggests that dietary factors may play a larger role in some cases of schizophrenia than is commonly recognized.