ANN ARBOR, MI — A growing group of clinicians is asking a simple but provocative question: what if some mental health symptoms are tied not only to brain chemistry, but also to how the brain makes and uses energy? For people who have struggled with medications, that idea has opened the door to diet changes, especially keto, plus other metabolism-focused treatments that are now being studied in small but expanding trials.
The evidence is still early, and not every result points in the same direction. But patient experiences, lab work, and a growing research field called metabolic psychiatry are keeping the conversation alive.
1. A Michigan nurse practitioner found keto changed the rhythm of her mood
Julianne Armijo, a 39-year-old family nurse practitioner and nursing doctoral student in Ann Arbor, was diagnosed with severe bipolar disorder after years of being treated at first for depression. Even with medications, symptoms kept breaking through, including one episode four years ago when she was jumping on construction equipment at 3 a.m. and seeing trees as if they were sparkling and breathing.
After learning about ketogenic diets in nursing school, she tried one three years ago. Within a couple of weeks, she noticed a difference and says the change felt life-changing, because her moods shifted from extreme peaks and valleys to something closer to ordinary, manageable variation.
2. Researchers say the brain may run better when it burns fat
Metabolic psychiatry starts from the idea that some brains may have trouble using glucose properly. Shebani Sethi, a psychiatric researcher at Stanford University, says that in conditions including bipolar disorder, schizophrenia, and Alzheimer’s, cells may be left “starving” because they cannot process sugar the way they should.
The theory is that ketones, which are produced when the body burns fat, can provide another fuel source. That does not prove keto helps everyone, but it offers a biological explanation for why some patients report fewer symptoms when their diet changes.
3. Keto is a strict diet, not just a trendy eating plan
A ketogenic diet is very different from the carbohydrate-heavy patterns many Americans recognize as normal eating, or even from a Mediterranean-style plan. In the version described in the story, about 60 percent of calories come from fat, around 30 percent from protein, and only about 10 percent from carbohydrates.
That means cutting out most grains, sweet fruit, legumes, potatoes, starchy vegetables, and many processed foods. The goal is ketosis, a state where the liver turns fat into ketones that can cross into the brain and replace glucose as fuel.
4. Small clinical trials are showing encouraging but uneven results
Sethi has helped build the research base with small studies. In her latest trial, published in May, several dozen people with bipolar disorder or schizophrenia-spectrum disorders improved in both depressive symptoms and cognitive performance after one month on the diet, performing better than people who stayed on their usual food.
Earlier pilot studies published in 2024 and last year also found that depression and other psychiatric symptoms eased after a few months. But the picture is not uniformly positive: a February study found that people with clinical depression on keto for six weeks did only slightly better than a group eating a somewhat healthier version of their regular diet.
5. Many doctors are interested, but not convinced yet
Some psychiatrists are still cautious. Mark Taylor, a private-practice psychiatrist in Edinburgh, reviewed the science for a nutrition-and-mood article and said he is not persuaded the evidence base is strong enough to recommend keto broadly right now.
Even so, the field is moving quickly. Researchers are running dozens of studies on post-traumatic stress disorder, autism-spectrum disorder, Alzheimer’s, mood disorders, and related conditions. Sethi is also starting a larger study with 120 participants who have schizophrenia, bipolar disorder, or major depression.
6. Blood sugar, insulin resistance, and mental illness may be linked
Another reason the topic is drawing attention is that metabolic illness and psychiatric illness often travel together. People with major psychiatric disorders have higher rates of metabolic disease, and the reverse is also true. One long Dutch study found that people with insulin resistance were twice as likely to develop major depressive disorder as those without it.
Sethi says she first saw the connection in training, when a keto diet suggested for an overweight patient with diabetes and treatment-resistant schizophrenia helped not only blood sugar and weight, but psychiatric symptoms too. The idea is that if insulin cannot help glucose enter brain cells, ketones may get around that problem.
7. Diet is only one part of a wider metabolism strategy
Researchers are also looking beyond keto. In Sweden, Mark Taylor analyzed data from people with diabetes and diagnosed depression or anxiety who took GLP-1 drugs to control blood sugar. Those patients had fewer episodes of psychiatric illness over 13 years, with especially strong results among people taking semaglutide medications such as Ozempic.
Other work points to gut bacteria, intermittent fasting, exercise, and sleep. A review last year linked different gut microbiome patterns with bipolar disorder, while early studies suggest fasting may reduce anxiety. Ede also notes that high-intensity workouts can help metabolism, and that chronic insomnia raises depression risk.
8. The biggest takeaway is promise, not a miracle cure
Armijo’s own experience shows both the appeal and the limits of the approach. Working with her doctor, she was able to taper off an antipsychotic that had made her feel sluggish and slowed down. She now follows keto closely, leaning plant-based with coconut oil, avocado, tofu, and macadamia nuts, and says the change in quality of life has been dramatic.
Still, she and the doctors quoted in the story emphasize that keto is not a cure. It requires ongoing attention to sleep, stress, social connection, and blood tests for cholesterol and other heart-related markers. For now, metabolic psychiatry is best understood as a promising tool under study, not a replacement for standard care.
