Does the body keep the score? Our brains and bodies are more linked than we knew

When analysing changes to the brain, they looked at the size and shape of brains, not their electrochemical functioning.

While poor body health, particularly of the metabolic, liver, and immune systems, was evident across all the disorders they looked at, it was most pronounced in people with schizophrenia.

Tian adds that diabetes is two to three times more common in people with a psychotic illness, such as schizophrenia or bipolar disorder, compared to the general population; similarly, people with schizophrenia have approximately two-fold increased risk of developing coronary heart disease, compared to people without mental illness; and one in five patients with heart failure are diagnosed with depression.

Despite this, poor physical health in people with mental illness tends to be overlooked or dismissed as a symptom of a psychiatric problem.

Though the paper doesn’t examine why there is such an overlap between physical and mental health, Tian suspects that it cuts both ways.

“We speculate that the relationship between physical and mental is likely bidirectional and complex,” she says. “This means that poor physical health may potentially lead to decline in mental health, and conversely, mental illness may result in chronic physical illness.”

Baldwin adds: “Our mental health is a product of many factors, which we need to get better at measuring over time if we are ever going to truly understand how mental ill health develops.”

The findings reinforce the idea that mental health is a “whole-of-person phenomenon”, says Baldwin, who was not involved with the research.

“We have known this for decades, yet for some reason many doctors and researchers continue to treat body and mind as somehow separable,” he says. “Findings such as these provide irrefutable evidence and can guide mental health treatments into a more holistic era.”

This means targeting both brain and body in the treatment of mental ill health, something that van der Kolk, who is a fan of yoga, art therapy, dance, theatre, karate, eye movement desensitisation and tapping, would surely approve of.

This also means, alongside traditional treatments, addressing physical health issues as well as considering other methods of mood management, like diet and exercise.

“Exercise is a great treatment for some mental illnesses,” says Baldwin. “For some people with mild to moderate depression, exercise alone is an effective treatment. What is undeniable is that our mental health depends on our physical health in many ways. I always tell my clients that diet, sleep, and exercise are an essential part of recovery.”

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