Or so says this one researcher. 

https://www.zerohedge.com/medical/root-cause-mental-illness-harvard-professor

"Palmer relayed that he initially couldn’t believe switching to a low-carbohydrate, ketogenic diet could stop chronic auditory hallucinations and paranoid delusions. He quickly started using this intervention in other patients and saw similar—sometimes even more dramatic—results."

Drawing from decades of research on metabolism and mitochondria, Palmer believes that mental disorders are metabolic disorders of the brain. This means that these conditions are not permanent defects and can be corrected by identifying and addressing their root cause. This insight challenges the notion that conditions such as schizophrenia and bipolar disorder are lifelong disorders.

“People with labels such as schizophrenia and bipolar disorder can put their illnesses into remission, they can heal, and they can recover,” Palmer asserted.

“That goes against much of what we tell people today,” he added.

https://www.youtube.com/results?search_query=Dr.+Christopher+Palmer