In a recent study published by scientists at University College London (UCL), a connection has been made between gastrointestinal bacteria and mental health.

Of the 41 studies included in their analysis, four specifically looked at the link between a traditional Mediterranean diet and depression over time in 36,556 adults.

A 33 per cent that adhered to a plant-based diet inclusive of fruits, vegetables, nuts, fish and seafood – had lower risk of developing depression.

People that were more likely to follow a dietary style originating from or inspired by Mediterranean regions – such as Greece were found to be able to lower the risk of mental health issues.

The researchers, who worked with partners in Spain and Australia with Melbourne being home of the third largest Greek population outside Greece, published their report in Molecular Psychiatry, giving a comprehensive overview of current evidence on the links between what people eat and their mood.

“There is compelling evidence to show that there is a relationship between the quality of your diet and your mental health,” said lead author, Dr Camille Lassale of UCL’s Epidemiology and Public Health department.

“This relationship goes beyond the effect of diet on your body size or other aspects of health that can in turn affect your mood.”

“We aggregated results from a large number of studies and there is a clear pattern that following a healthier, plant-rich, anti-inflammatory diet can help in the prevention of depression,”  continued Dr Lassale.

The Greek diet is the most balanced amongst other Mediterranean cuisines as it contains the least amount of “pro-inflammatory” foods such as saturated fat, sugar and heavily processed products that were associated with a higher risk of depression in five studies of more than 32,000 adults.

“There is also emerging evidence that shows that the relationship between the gut and brain plays a key role in mental health and that this axis is modulated by gastrointestinal bacteria, which can be modified by our diet,” said Dr Lassale adding that the next step is to examine how dietary intervention actually affects mental health.

“There are now strong arguments in favour of regarding diet as mainstream in psychiatric medicine,” stressed the essay’s Co-author, Tasnime Akbaraly of France’s INSRM research centre,

“This is of importance at a patient’s level, but also at public health level, especially in a context where poor diet is now recognised to be the leading cause of early death across middle and high-income countries and at the same time mental disorders as the leading cause of disability.”