While more and more researchers are working on nutritional psychiatry, most studies fail to determine whether specific foods cause mental health to deteriorate or improve.
A healthy mind in a healthy body. Everyone knows the saying and everyone knows that eating well is very important for maintaining good health. But not just physical. More and more studies are linking food and mental health. Our brain needs nutrients to function and the food we eat influences factors related to mood, hormones and cognition. Unfortunately, in most of this work, it is impossible to determine whether the foods themselves cause a deterioration or an improvement in mental health, lament researchers in a recent article in the journal European Neuropsychopharmacology.
“We found that there is growing evidence of a link between poor diet and worsening mood disorders, including anxiety and depression. However, many common beliefs about the effects of certain foods on health are not supported by solid evidence”, explains Professor Suzanne Dickson, from the University of Gothenburg (Sweden) who conducted the study.
For example, it has been proven that people suffering from vitamin B12 deficiencies can suffer from lethargy, fatigue, memory problems or even psychosis. Vitamin B12 supplementation could therefore improve their mental well-being. On the other hand, it is still unclear whether this would make a difference for “healthy” people, note the authors of the study.
Evidence very hard to find
As for vitamin D, while some studies have found supplements may reduce the risk of depression, others have found it has no impact on mental health. Similarly, the evidence for the role of diet in attention deficit hyperactivity disorder (ADHD) is quite hazy.
“[N]We can see that increasing the amount of refined sugar in the diet seems to increase ADHD and hyperactivity, while eating more fresh fruits and vegetables seems to protect against these conditions. But there are relatively few studies, and many of them don’t last long enough to show long-term effects,” Professor Dickson says.
“There is a general belief that dietary advice for mental health is based on solid scientific evidence. In reality, it is very difficult to prove that specific diets or specific food components contribute to mental health,” she continues.
The benefits of the Mediterranean diet
A few well-controlled studies have succeeded in better proving the link between mental health and diet, but they generally take place over a short period of time and take into account a small number of participants.
Here, however, the researchers noted strong evidence that the Mediterranean diet would benefit mental health. “A systematic review combining a total of 20 longitudinal studies and 21 cross-sectional studies provided compelling evidence that a Mediterranean diet may confer a protective effect against depression,” the researchers note.
It is a traditional food practice in several countries around the Mediterranean Sea characterized by the abundant consumption of fruits, vegetables, legumes, whole grains, aromatic herbs, olive oil, fish and dairy products, a consumption moderate consumption of eggs and wine, and a low consumption of meat.
In this study, scientists also found strong evidence that certain dietary changes could help with disease. For example, children with drug-resistant epilepsy reportedly have fewer seizures when they follow a ketogenic, high-fat, low-carb diet.
“Nutritional psychiatry is a new field”
Overall, Professor Dickson concludes: “Nutritional psychiatry is a new field. The message of this article is that the effects of diet on mental health are real, but care should be taken not to jump to conclusions based on tentative evidence. We need more studies on the long-term effects of daily diets”. Because neuropsychiatric disorders represent “some of the most pressing societal challenges of our time”, “if it is possible to prevent or treat these conditions through simple dietary changes, it would change the lives of millions of people.”
For example, depression affects an estimated 300 million people. “It differs from the usual mood swings and fleeting emotional reactions to everyday problems. When it persists and its intensity is moderate or severe, depression can become a serious illness. It can cause great suffering, alter the professional, school and family life of the person concerned. In the worst case, depression can lead to suicide. Every year, nearly 800,000 people die by suicide,” explains WHO. And if there are treatments to fight it, less than half of the people affected in the world benefit from it. Whether it’s because of a lack of resources, a shortage of caregivers, or the social stigma attached to mental disorders.
.
