Stanford study shows keto diet can improve severe mental illness

A ketogenic diet not only restores metabolic health in patients with severe mental illness as they continue their medications, but it further improves their psychiatric conditions, according to a recent study by Stanford Medicine researchers.

The results, published on 27 March in Psychiatry Research, suggest that a dietary intervention can be a powerful aid in treating mental illness, reports the Stanford Medicine News Center.

For people living with serious mental illness like schizophrenia or bipolar disorder, standard treatment with antipsychotic medications can be a double-edged sword. While these drugs help regulate brain chemistry, they often cause metabolic side effects such as insulin resistance and obesity, which are distressing enough that many patients stop taking the medications, according to the report.

Shebani Sethi, MD, associate professor of psychiatry and behavioural sciences and the first author of the new paper, said, "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." 

"The ketogenic diet has been proven to be effective for treatment-resistant epileptic seizures by reducing the excitability of neurons in the brain," Sethi said. "We thought it would be worth exploring this treatment in psychiatric conditions."

Sethi coined the term metabolic psychiatry, a new field that approaches mental health from an energy conversion perspective.

In the four-month pilot trial, Sethi's team followed 21 adult participants who were diagnosed with schizophrenia or bipolar disorder, taking antipsychotic medications, and had a metabolic abnormality — such as weight gain, insulin resistance, hypertriglyceridemia, dyslipidemia or impaired glucose tolerance. The participants were instructed to follow a ketogenic diet, with approximately 10% of the calories from carbohydrates, 30% from protein and 60% from fat. They were not told to count calories.

"The focus of eating is on whole non-processed foods including protein and non-starchy vegetables, and not restricting fats," said Sethi, who shared keto-friendly meal ideas with the participants. They were also given keto cookbooks and access to a health coach. 

The research team tracked how well the participants followed the diet through weekly measures of blood ketone levels. By the end of the trial, 14 patients had been fully adherent, six were semi-adherent and only one was non-adherent.

The participants underwent a variety of psychiatric and metabolic assessments throughout the trial.

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

The psychiatric benefits were also striking. Overall, the participants also reported better sleep and greater life satisfaction, the study finds.

"The participants reported improvements in their energy, sleep, mood and quality of life," Sethi said. 

"They feel healthier and more hopeful…We saw more benefit with the adherent group compared with the semi-adherent group, indicating a potential dose-response relationship," Sethi said.

There is increasing evidence that psychiatric diseases such as schizophrenia and bipolar disorder stem from metabolic deficits in the brain, which affect the excitability of neurons, Sethi said.

The researchers hypothesise that just as a ketogenic diet improves the rest of the body's metabolism, it also improves the brain's metabolism.

"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."

Likely there are multiple mechanisms at work, she added, and the main purpose of the small pilot trial is to help researchers detect signals that will guide the design of larger, more robust studies.  

"Many of my patients suffer from both illnesses, so my desire was to see if metabolic interventions could help them," she said. "They are seeking more help. They are looking to just feel better."

Researchers from the University of Michigan; the University of California, San Francisco; and Duke University contributed to the study.

The study was supported by Baszucki Group Research Fund, the Kuen Lau Fund and the Obesity Treatment Foundation.