Patients with schizophrenia or bipolar disorder tend to see their conditions ease after four months on the ketogenic (“keto”) diet, a small pilot study finds.

While no one is saying the diet should replace standard medications, the researchers believe it could provide additional help for some.

“It’s very promising and very encouraging that you can take back control of your illness in some way, aside from the usual standard of care,” said study first author Dr. Shebani Sethi. She’s an associate professor of psychiatry and behavioral sciences at Stanford University.

The findings were published March 27 in the journal Psychiatric Research.

Sethi said she first noticed there might be a connection between the keto diet and psychiatric health when she was working as a student in a clinic focused on obesity and weight loss.

Many people with psychiatric conditions gain excess weight due to medication side effects. Sethi was helping to treat one such patient, who had schizophrenia.

The patient’s auditory hallucinations (“hearing voices” can be a common symptom of schizophrenia) quieted down after being on the keto diet, she said.

A search of the literature turned up little regarding using the diet to counter schizophrenia, but there was evidence it could ease epileptic seizures.

Apparently the diet did so “by reducing the excitability of neurons in the brain,” Sethi explained in a Stanford news release. “We thought it would be worth exploring this treatment in psychiatric conditions.”

The new trial was small — just 21 adults diagnosed with either schizophrenia or bipolar disorder. All were on medication for their conditions and also had excess weight gain, troubles with high cholesterol or blood sugar control and/or insulin resistance.

They were all told to follow the ketogenic diet — in this case, a regimen that included about 10% of calories coming from carbohydrates, 30% from protein and 60% from fat.

“The focus of eating is on whole non-processed foods including protein and non-starchy vegetables, and not restricting fats,” explained Sethi. Participants received keto cookbooks and access to a health coach. 

Blood tests were used to measure just how closely folks stuck to the regimen.

Weight loss was the first big plus: Participants lost an average of 10% of their body weight and 11% off their waistline measurements, the researchers reported.

Patients also benefited from reductions in blood pressure, triglycerides (a kind of blood fat), blood sugar levels and insulin resistance.

“We’re seeing huge changes,” Sethi said. “Even if you’re on antipsychotic drugs, we can still reverse the obesity, the metabolic syndrome, the insulin resistance. I think that’s very encouraging for patients.”

Patients’ brains seemed to benefit, too.

“The participants reported improvements in their energy, sleep, mood and quality of life,” Sethi said. “They feel healthier and more hopeful.”

Mental benefits were tracked using what’s know as the clinical global impressions scale. On average, folks on the keto diet saw a 31% improvement in scores, the Stanford team said.

Just how is a change in diet helping?

According to Sethi, evidence is gathering that illnesses such as schizophrenia and bipolar disorder may stem, in part, from metabolic deficits in the brain, which affect neuronal “excitability.”

“Anything that improves metabolic health in general is probably going to improve brain health anyway,” Sethi said. “But the ketogenic diet can provide ketones as an alternative fuel to glucose for a brain with energy dysfunction.”

Most people were also able to stick to the keto diet, the study found. Fourteen of the 21 participants were “fully adherent,” six were semi-adherent and only one was non-adherent.

More information

Find out more about the ketogenic diet at Harvard Health.

SOURCE: Stanford University, news release, April 1, 2024

Source: HealthDay