The results of a ten year study suggest that eating a Mediterranean diet could prevent depression.

The research, conducted by the Department of Preventative Medicine and Public Health at the University of Navarra in Northern Spain involved 15,000 participants who helped the researchers to identify possible links between diet and health factors including diabetes and depression. The research, named the SUN project, began in 1999 with the participants completing questionnaires, and then returning to complete further questions bi-annually. They were also required to follow one of three diets, which included:

  • The Mediterranean diet
  • The pro-vegetarian dietary pattern, or;
  • The alternative healthy eating index – 2010.

All these diets could be described at the most basic level as “healthy diets” due to their high levels of nutrition, rich in nuts, legumes, fruit and vegetables and low in saturated fats and trans-fatty acids. Researchers were able to assess how closely the participants adhered to their chosen diet through a scoring system.

Of the 15,000 participants, zero reported having any episodes of depression at the start of the study. At the eight year mark, 1550 had either been diagnosed with clinical depression or had been prescribed anti-depressants. The results found that those who had followed the Mediterranean diet, or the alternative healthy eating index were the least susceptible to depression. However, what is arguably the most interesting element of this study is that those who followed the diets moderately as opposed to strictly saw greater mental health benefits.

“The noticeable difference [in depression risk] occurs when participants start to follow a healthier diet. Even a moderate adherence to these healthy dietary patterns was associated with an important reduction in the risk of developing depression. However, we saw no extra benefit when participants showed high or very high adherence to the diets.”

Lead Researcher – Almudena Sanchez-Villegas

What Is It About The Mediterranean Diet That Benefits Our Mental Health?

This question is a source of much debate between scientists and there are several theories as to why a Mediterranean diet may improve our mental wellbeing. Some believe that the rich content of omega 3 fatty acids present in the Mediterranean diet keeps depression at bay due to its anti-inflammatory properties. Omega 3 fatty acids can prevent cells from inflaming, which is significant since depression is linked to brain inflammation. Some believe it is the broadness of the Mediterranean diet, which provides a rich cross section of nutrients from a wide number of healthy sources. Not only is it the breadth of different nutrients so prevalent within the Mediterranean diet, but also that the foods that feature so strongly, including olives, fish and often organic green vegetables and herbs are particularly rich in nutrients. Furthermore, those who displayed the best results in terms of mental health wellbeing, also drank moderate levels of alcohol – notably red wine.

While this research does not make a concrete link between the Mediterranean diet and a reduced risk of depression, the correlations are significant. Taking into consideration the previous studies that have been conducted within the field it would appear that the Mediterranean diet has wide reaching health benefits, on the mind as well as the body.

For more information about the links between healthy eating and depression, and to find out what you could be eating more or less of to beat depression, please visit NHS Choices.