Switching to a healthy Mediterranean diet can help reverse the symptoms of depression, a study finds.
Young men with moderate to severe depression in the clinical trial swapped out processed red meats, sugar and fast foods.
Instead, they ate colourful vegetables, wholegrains, fish and raw, unsalted nuts (see: the MIND diet).
One way dietary change may help reverse depression is by affective levels of serotonin, the neurotransmitter that is central to mood.
Higher quality of life
For the research, 72 depressed young men were assigned to either a dietary change group or a control group that consisted of ‘befriending’.
Ms Jessica Bayes, the study’s first author, said:
“We were surprised by how willing the young men were to take on a new diet.
Those assigned to the Mediterranean diet were able to significantly change their original diets, under the guidance of a nutritionist, over a short time frame.
It suggests that medical doctors and psychologists should consider referring depressed young men to a nutritionist or dietitian as an important component of treating clinical depression.”
After 12 weeks, the results revealed that changing to the Mediterranean diet reduced depressing significantly more than befriending.
The young men also rated their quality of life as higher after changing their diet.
Ms Bayes explained the importance of diet:
“The primary focus was on increasing diet quality with fresh wholefoods while reducing the intake of ‘fast’ foods, sugar and processed red meat.
There are lots of reasons why scientifically we think food affects mood.
For example, around 90 per cent of serotonin, a chemical that helps us feel happy, is made in our gut by our gut microbes.
There is emerging evidence that these microbes can communicate to the brain via the vagus nerve, in what is called the gut-brain axis.
To have beneficial microbes, we need to feed them fibre, which is found in legumes, fruits and vegetables.”
Around 30 percent of people do not respond to standard depression treatment, such as medication and/or cognitive-behavioural therapy.
Ms Bayes said:
“Nearly all our participants stayed with the program, and many were keen to continue the diet once the study ended, which shows how effective, tolerable and worthwhile they found the intervention.”
Diet and mental health
Hundreds of studies have linked a better diet with improved mental health.
For example, studies have shown a link between a diet rich in vegetables, nuts, fruits and fish and a lower risk of depression.
Raw fruits and vegetables in particular have been linked to better mental health.
Reducing the intake of common inflammatory foods including fast food, cake and processed meats reduces the risk of depression.
Similarly, cutting down on refined carbohydrates, such as white bread, white rice and soda, may lower depression risk.
All sorts of positive dietary changes, including weight loss, fat reduction and nutrient boosting diets, have been shown to improve mental health.
The study was published in The American Journal of Clinical Nutrition (Bayes et al., 2022).