Proof That Diet Has a Positive Effect on Mental Health

Some of us love science and need a gold standard randomise trial and others just need to see and feel the evidence. Here at A Healthy View we have both!

A Mediterranean-style diet supplemented with fish oil can improve mental health in people with depression, a study shows. The South Australian researchers say this is one of the first randomised controlled trials to find a casual effect.

Adults with self-reported depression were randomised to eat a Mediterranean diet for three months and take fish oil supplements for six months or to attend social groups fortnightly for three months.

Both groups showed improved mental health, but reduced depressive symptoms were significantly greater in the diet group.

Depression scores improved by 45% in the Mediterranean diet group and 26.8% in the social group.

“This equates to 1.68 times greater improvement in depressive symptoms in the Mediterranean diet group,” the authors write.

Senior research fellow and study leader Dr Natalie Parletta say the findings confirm an association between diet and mental health. 

“It makes sense that diet can impact mental health,” she says, adding that this notion has previously attracted scepticism. “Dietary nutrients — including vitamins, minerals, polyunsaturated fats and amino acids — are essential for healthy brain structure and function." Dr Parletta says factors that underpin poor physical health, such as inflammation, glucose intolerance, impaired cerebral blood flow and oxidative stress, also affect mental health. These are all related to poor diet, she adds.