Revision in 'The Lancet Psychiatry'

Nutrition has become a key factor explaining the high prevalence and incidence of very common mental illnesses such as depression.

According to Vincent Balanzá, Professor of Psychiatry at the University of Valencia.

A scientific review conducted by members of the International Society of Nutritional Psychiatry Research (ISNPR) and published in The Lancet Psychiatry has confirmed that the quality of the diet and deficiencies in certain essential nutrients are basic determinants for physical health, but also for mental health. According to Vincent Balanzá, Professor of Psychiatry at the University of Valencia and member of the executive committee of the ISNPR, "nutrition has become a key factor for the high prevalence and incidence of very common mental illnesses such as depression."

Balanzá, from the Biomedical Research Network Centre in Mental Health (Cibersam), has stressed that to achieve optimal brain functioning, "the human brain needs adequate intake of key nutrients, such as long-chain polyunsaturated omega-3 fatty acids, essential amino acids, group B vitamins (folic acid and B12), vitamin D and minerals such as zinc, magnesium and iron." In this context, "a balanced and high-quality diet, such as the Mediterranean diet, provides these nutrients; we have evidence that it reduces the risk of depression."

Relation between nutrition and mental health

Historically, "the relationship between nutrition and mental health was ignored or studied in a less rigorous way. However, in recent years, solid scientific evidence has accumulated that suggests that the diet and these essential nutrients play a prominent role in the etiology and treatment of common illnesses, such as depression."

The relationship between the quality of the diet and depression is based on numerous epidemiological studies conducted in various countries: "Reviews and meta-analyzes show clear trends regarding two major dietary patterns. On the one hand, low-quality diets, such as those based on highly processed foods, are associated with an increased risk of depression and poorer mental health. On the other hand, the higher the adherence to high-quality diets, such as the Mediterranean diet, the lower the risk of developing depression. This was the conclusion of the well-known SUN cohort study, published by Almudena Sánchez-Villegas and colleagues."

Clinical trials

However, the relationship between diet and mental health is complex and bidirectional, and to establish causality relationships, "clinical trials are needed to examine the effects of dietary interventions." At this time, "it cannot be said that depression is cured solely with a healthy diet." On the other hand, from the ISNPR, we propose that the next clinical trials in this field "include biomarkers," since "we need to unravel the biological mechanisms that explain the efficacy of essential nutrients." There is evidence that they can reduce oxidative stress and positively influence the functioning of the immune system and neurotrophins, proteins such as BDNF that increase neuron resistance to stress. "All these molecular pathways are involved in the pathogenesis of depression and other mental illnesses."

Information obtained from:

Enrique Mezquita