Whoever brought a book discussing the ketogenic diet to a homeless shelter in the United Kingdom may have done one of its residents a big favor. A 32-year-old homeless man with schizophrenia read it and was so inspired that he began experimenting with the diet in an effort to control his symptoms.

In this case report, published this June in Frontiers in Nutrition, a nutritional therapy specialist in the United Kingdom that he later consulted found he had derived little benefit from medications. With her help and others, he began regular ketogenic metabolic therapy (KMT), which involves a diet high in fat, moderate in protein and very low in carbohydrates, prompting the body’s metabolism to go from running mostly on glucose, the sugar that makes up most carbs, to using ketones, a metabolite of fat, as its primary fuel. 

The patient had been diagnosed with paranoid schizophrenia, and later, PTSD. After the death of a close family member, he developed paranoid delusions, suicidal thoughts and psychotic episodes that eventually left him unable to work and homeless, and he moved in and out of hospital for three years. His hospital treatment included medication and group and occupational therapy, which included trips to cafes and museums. But far from boosting his mental health, he felt that he deteriorated as an inpatient.

Then, in a homeless shelter, he discovered the self-help book that talked about the ketogenic diet and decided to try it, without any expectation that it could help with his schizophrenia. In the shelter, he had his own room as well as access to a mini-fridge and a portable grill, and he experimented with a carnivore ketogenic diet (based solely on meats and fats). He noticed that ‘cheat’ days, where he consumed a lot of sugar and chocolate, came with problems in mood and behavior. 

After further experimentation in a rehab facility, he decided to consult a nutritional specialist versed in KMT and see whether his psychiatrist might support it as part of his therapy. Tests found his blood glucose and ketone readings to be erratic, “so the aim was to stabilize his glucose levels and optimize his ketones in the therapeutic range,” according to author Moira Newiss, a registered nutritional therapy practitioner.

He worked with the specialist to get his readings under control, and from June 2024 on, “managed by himself without practitioner support.” He continued his carnivore ketogenic diet, got regular blood tests, and began tapering off his psychiatric medications after seven months. In late October 2024, the case report states, “his mental health team noted his schizophrenia was in remission. He has had no psychotic episodes since he started the ketogenic diet on his discharge from hospital, a period of over nine months. He has come off all his psychiatric medications and remains stable.”

As the paper notes, people with schizophrenia have a significantly higher risk of obesity and a diabetes prevalence two to three times higher than the general population. “Signs of metabolic syndrome were first identified in patients with schizophrenia over 100 years ago and current day use of antipsychotic medication comes with a major side effect of increasing metabolic dysregulation,” Newiss said. This patient’s carnivore ketogenic diet was “life-changing and lifesaving,” she wrote.

Newiss added that information about the therapy should be made available to other patients. Although it was too early to recommend this particular meat-and-meat fat-based keto diet to other patients, she added, further research was warranted. (See MindSite News’ recent article on KMT’s potential for treatment in serious mental illnesses.)