S

chizophrenia has long been treated, with limited

success, with drugs that block the brain neuro-

transmitter dopamine. Pharmaceutical companies

have spent billions of dollars developing yet another

drug with a slightly different mechanism of action to

also block dopamine transmission.

Is it possible that a dietary intervention can help people

suffering from this devastating mental illness, or is this idea no

better than the fad diets promoted in the pages of celebrity

gossip magazines?

Our research found that the ketogenic diet, which is very

high in fat and extremely low in carbohydrates, effectively

normalised a wide range of schizophrenia-like behaviours in a

well-established mouse model of the disorder.

What does this diet do that makes the symptoms disappear?

Is this approach safely translatable to humans?

I think it is translatable, and there is some fascinating new

science behind it as well.

Beyond Dopamine

I was in the middle of my psychiatry rotation in the last year of

medical school when my brother told me of the strange, highly

disturbing behaviour of his classmate. “He locks himself in his

room, closes the curtains and the shutters on the window. He

does not talk to his mother and has not been taking much food

for a week in the fear of being poisoned. When he does talk he

is talking nonsense about some voices he is hearing.”

The very next morning, an 18-year-old man was taken to

our psychiatry ward. He was very agitated and needed to be

physically restrained by police. He attacked his mother because

he thought she wanted to kill him.

He was my brother’s classmate. He was diagnosed with an

acute psychotic episode, promptly received an antipsychotic

injection and admitted to the ward.

I soon moved on to another rotation and a year later acci-

dentally bumped into the psychiatrist who had admitted the

young man. I asked him about his young patient.

“He died, unfortunately... committed suicide,” the psychi-

atrist answered.

“But he was looked after properly, received his antipsychotic

medication and should have not ended up like this,” I protested

in my youthful enthusiasm.

Perhaps now, one-quarter of a century later, we are in a much

better position to help people who are suffering from this devas-

tating mental illness.

For many years, schizophrenia research and drug develop-

ment was driven by the idea that there seems to be an increased

activity of dopamine in the brain. A lot of evidence pointed in

that direction. For example, drugs used in the treatment of

schizophrenia all blocked the receptor protein for dopamine,

and drugs that stimulated brain dopamine tend to induce

psychosis.

Animal models with hyperactive dopamine neurotrans-

mission churned out drugs that all resembled the original

antipsychotics used in the validation of these animal models

in the irst place. A bit of a Catch 22, isn’t it?

Then, in the dawn of the “genomic age”’ at the turn of the

millennium, human genetics research started to uncover a

number of other possible disease mechanisms. Researchers

started to discover schizophrenia susceptibility genes that play

a role in brain development and in the formation of the synapse

that connects one nerve cell to the next. They also identiied that

14 | MAY 2016

A Diet that Calms the

Schizophrenic Mind

ZOLTÁN SARNYAI

The ketogenic diet favoured by bodybuilders also normalises schizophrenia-like behaviours.

Ketogenic Diet Warning!

The typical ketogenic diet (also called the “long-chain

triglyceride diet”) is a high-fat, low-carbohydrate diet that has

been in use since 1921.

The diet provides 3–4 grams of fat for every 1 gram of

carbohydrate and protein. It is provided by a medical

practitioner working together with a registered dietitian, and

should NOT be done without medical supervision.

The diet itself is challenging, especially at the beginning. It

requires strict compliance, precise food measurements, a

hospital stay for observation and plenty of patience.