Poor nutrition leads to poor health.

However, a growing body of research is suggesting that eating healthy not only affects waistlines, but can lower the risk of depression and suicide – ultimately, helping with mental health.

For instance, foods like fruits, vegetables and whole grains may contribute to better mental health, compared to personal comfort foods that bring about joy and satisfaction.

What does research say?

In 2015, researchers wrote in a review (published in The Lancet) that "although the determinants of mental health are complex, the emerging and compelling evidence for nutrition as a crucial factor in the high prevalence and incidence of mental disorders, suggests that diet is as important to psychiatry as it is to cardiology, endocrinology, and gastroenterology."

Similarly, Laurel Cherian of Rush University Medical Centre in Chicago, suggested that the popular Dietary Approaches to Stop Hypertension (DASH) diet – which was created to lower blood pressure – may be able to reduce the risk of depression in adults by 11%. This was compared to a Western diet, rich in saturated fats and meat – found more likely to develop depression – and a Mediterranean diet.

The DASH diet has been associated to a lower risk of depression. Photo credit: Gill Heart Institute/Source: UK National Heart, Lung and Blood Institute
The DASH diet has been associated to a lower risk of depression. Photo credit: Gill Heart Institute/Source: UK National Heart, Lung and Blood Institute

However, Cherian highlighted that, "future studies are now needed to confirm these results and to determine the best nutritional components of the DASH diet to prevent depression later in life and to best help people keep their brains healthy.”

With an increasing amount of such scientific evidence, it is no surprise that the discipline of nutrition psychiatry – which focuses on the use of food and supplements to provide essential nutrients as part of or an alternative treatment for mental health disorders – is indeed growing. But these approaches are not as widely accepted by mainstream medicine.

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Brain health: It all begins in the gut

On the most basic level, food provides nutrients, which affect various bodily functions – and by extension, mood, as well. An example of this is the positive effect of nutrition on the immune system – which can influence the risk of depression.

"When people are feeling better by dieting and losing weight or resolving symptoms that they’re having, that could have an impact on mood," said Dr Sherry Pagoto, a clinical psychologist and professor at the University of Connecticut.

Dr Sherry Pagoto a clinical psychologist and professor at the University of Connecticut says,
Dr Sherry Pagoto a clinical psychologist and professor at the University of Connecticut says, "When people do engage in healthy lifestyle changes, we do see improvements in depression." Photo credit: University of Massachusetts Medical School

The link between poor mental health and nutritional deficiencies has been recognised by nutritionists in the complementary health sector. However, psychiatrists are now only becoming increasingly aware of the benefits of using nutritional approaches to mental health – especially, when it is now known that many mental health conditions are caused by inflammation in the brain, killing off brain cells.

The inflammatory response begins in the gut, often by the lack of nutrients from food such as magnesium, omega-3 fatty acids, probiotics, vitamins and minerals, essential for the optimum functioning of the body.

This may explain why Mediterranean and DASH diets, that feature fish, vegetables and olive oil, can positively affect mental health. Furthermore, those foods are anti-inflammatory, which can combat the higher levels of C-reactive protein – a marker of inflammation – often found in depressed individuals.

Whereas, Western diet staples like white bread, red meat and fried foods can cause inflammation in the body and should be eaten minimally or avoided.

Nutritional psychiatry to provide a fresh perspective

“For people who have not responded to prescription drugs or who cannot tolerate the side effects, nutritional intervention can offer hope for the future,” says Joyce Cavaye, Senior Lecturer in Health, Well-Being and Social Care at The Open University, in the UK.

True to that statement, there is much debate over the effectiveness of antidepressants. Medical education has also traditionally excluded nutritional knowledge and its association with disease. As such, nutritional interventions are thought to have little evidence to prevent or maintain well-being, leaving the job to dietitians, rather than doctors to advise on.

However, with new research building up, doctors should perhaps take nutrition more seriously. Who knows, nutritional psychiatry may even offer a “one-fit-for-all” approach, targeting the mental health of all age groups. MIMS

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