Can the keto diet really improve mental health?

Maya Schumer, 32, a neuroscientist in Belmont, Massachusetts, was living with bipolar disorder for more than a decade. She had tried nearly every treatment — therapy, anti psychotics, mood stabilisers, anticonvulsants — to help control her symptoms.

But her panic attacks, mania, depression and brain fog still lingered.

By 2024, she said, she was “the most suicidal” she had ever been. So when her psychiatrist suggested she try the ketogenic diet, which focuses on high-fat, low-carbohydrate foods, she decided she had nothing left to lose.

Within five months of eating more foods high in fat such as red meat, butter and avocado and fewer grains, fruits and vegetables, her panic attacks decreased and she could focus without using a stimulant, she said. Her depression persisted, however, so her psychiatrist added a low dose of lithium. Finally, with a combination of diet and medication, she said, “things clicked.” She described feeling stable, secure and grounded, and her illness seemed easier to manage. She likened it to being able to see without glasses.

In recent years, some limited studies have started to suggest that the keto diet may help reduce symptoms of mental illnesses like depression, bipolar disorder and schizophrenia. In February, Health Secretary Robert F. Kennedy Jr. even claimed that it could “cure” some of these conditions.

Experts say that there is no evidence to support his statement and that the diet should not replace proven treatments like therapy or psychiatric medications. But some people — especially those who haven’t had much success with the medications or who have experienced severe side effects — say they are desperate for other solutions. Now, doctors and patients have started to experiment with keto for mental illness treatment.

A cellular ‘switch’

The ketogenic diet has been used since the 1920s as a treatment for epilepsy, though it is better known and more commonly used today for weight loss.

There are many versions of the diet, but all recommend eating high-fat, low-carbohydrate foods such as eggs, meat, fish, butter, nuts and nonstarchy vegetables including leafy greens and cauliflower. Grains, legumes, sweets, most fruits and starchy vegetables such as potatoes are off limits.

The goal is to put the body into ketosis — when cells “switch” from mainly burning carbohydrates for energy to burning fat for energy, said Dr. Shebani Sethi, director of the metabolic psychiatry program at Stanford Medicine. This stabilises and lowers blood sugar and insulin levels and may reduce appetite, which could help with weight loss and managing Type 2 diabetes.

In 2017, Dr. Christopher Palmer, an assistant professor of psychiatry at Harvard Medical School, reported a link between the diet and mental health, publishing a case study involving two of his patients with schizoaffective disorder.

Both patients found that their depression lifted and their hallucinations and delusions faded after trying the keto diet for a few weeks. When they stopped the diet, their symptoms returned within 24 hours.

“My initial reaction was disbelief — like, this is impossible,” Palmer said. “Then I dove into the literature.” He found only a few scientific studies on keto and mental illness, he said, including a 1965 trial involving 10 women with schizophrenia whose symptoms improved after following the diet for two weeks.

Lewis Anstee, 31, who lives in Britain, tried the keto diet in 2024, the same year he was diagnosed with schizophrenia. At first, he said, he felt somewhat better but didn’t know how to stick with it. Eventually, he learned what worked for him, and he noticed that when he followed the diet closely, his paranoia and delusions faded. He felt so much better that he worked with a psychiatrist to wean off his medication, which had caused him to feel numb and sedated.

“The side effects, for me, far outweigh any potential benefit” of the medication, he said.

Research on the diet’s success in treating epilepsy has suggested that keto seems to stabilise brain cells, reduce inflammation and balance the levels of neurotransmitters in the brain, Palmer said. Some small and limited studies have supported the hypothesis that such brain changes could help people with mental illness, too.

In a 2024 trial, researchers assessed the symptoms of 23 adults with schizophrenia or bipolar disorder before and after they followed the keto diet for four months. At the end of the study, the researchers reported that participants’ symptoms had improved by an average of 31 per cent. Another study, published in 2025, concluded that when 16 college students with major depression followed the diet for 10 to 12 weeks, their symptoms improved by around 70 per cent.

Many participants in these and other studies lost weight while on the diet and had other health improvements, like lowered blood pressure and inflammation levels, which may have — at least in part — led to better brain functioning that could have helped their symptoms, said Sethi, who led the 2024 trial.

It’s also possible that these positive results were partly because of a placebo effect — or a phenomenon where a person’s health improves based on a belief that a treatment will make them feel better, said Min Gao, a senior researcher in metabolic psychiatry at the University of Oxford. Because neither study included a control group, she said, it’s hard to rely on the conclusions.

In a trial published in February that involved 88 people with clinical depression, Gao and her colleagues did include a control group. They gave half of the participants ketogenic meals for six weeks and asked the other half (the control group) to eat slightly healthier than they usually did. While the depressive symptoms in the keto group improved compared with the control group, Gao said, it was by only a slim margin.

Far more research is needed to determine the effects of the keto diet on mental health, she added.

Weighing the Risks and Benefits

At least a dozen trials about keto and mental illness are underway or have recently been completed.

Some experts say they will not be convinced of the diet’s benefits until more is known, and worry it may come with some risks. If patients try the diet on their own and start to feel better, they may think they can stop taking their medications, which could lead to worsening symptoms or a mental health crisis, said Dr. Gia Merlo, a clinical professor of psychiatry at the NYU Grossman School of Medicine.

Dr. Drew Ramsey, a psychiatrist who specializes in nutrition in Jackson, Wyoming, recalled a former patient with bipolar disorder who “became enamored” with keto, stopped his medications while trying the diet and was later hospitalised with mania. “It doesn’t work for everyone,” Ramsey said.

Popular versions of the keto diet also tend to be high in saturated fats, like from red meat, and low in fibre, which may increase the risk of health conditions such as cardiovascular disease and some types of cancer, Merlo added.

Another challenge is that the keto diet can be hard to follow long-term, Ramsey said. It often requires cooking from scratch, diligently tracking nutrients and avoiding many foods people enjoy, like rice, bread and most fruits. Even those who have support from dietary coaches or who participate in scientific studies sometimes decide to quit.

If you want to try the diet, it’s important to do so under the guidance of a physician or other provider, Palmer said, who can monitor your health and make any medication adjustments if needed. “Please do not do this on your own,” he added.

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That said, some patients have so much success with keto that they stick with it for years, Palmer said.

Schumer has been following the diet for 18 months, and she plans to continue.

“If this diet can help me live,” she said, “things like bread and pasta didn’t really seem that important.”

This article originally appeared in The New York Times.

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