An unhealthy diet increases the risk of developing depression.

For several years now, the prevalence of depressive disorders has been increasing worldwide and represents a growing public health problem. According to recent estimates, 4% (≈280 million) of the global population before the pandemic suffered from some form of depressive disorder, a figure that far exceeds those reported in 1990 (3%, ≈180 million). What's more, with the pandemic, at least 53 million additional cases of major depression have been added.

These depressive disorders can have a significant impact on overall well-being, impairing individuals' physical and psychosocial functioning. Is there a remedy? Can we reduce these figures? It is clear that slowing down the fast pace of life, combating stress, avoiding social isolation and promoting contact with nature helps. However, there is another factor that we do not usually consider when thinking about preventing depression: diet.

What is an inflammatory diet and how is it related to depression?

In recent years, lifestyle behaviours such as diet have received special attention as feasible everyday strategies for preventing depression. But are we clear about which diet is right for our mood and which is not?

The worldwide increase in unhealthy (and sedentary) eating habits has created a large-scale global challenge that disrupts the energy balance and accessibility to natural foods that have been important sources of healthy nutrients throughout human history. I am referring to fruits, nuts, vegetables and whole grains. This has led us away from one of the most scientifically proven optimal dietary patterns for health: the Mediterranean diet, rooted in a thousand-year-old intercultural culinary tradition. Instead, we tend to adopt suboptimal diets in which we overindulge in ultra-processed foods high in sodium, added sugars and trans fats. This poses a significant danger, as excessive consumption of these types of foods causes our innate immune system to release pro-inflammatory cytokines which, among other things, increase the incidence of certain types of cancer, metabolic syndrome, type 2 diabetes, cardiovascular disease, neurodegenerative diseases and depression. Our articles are accessible free of charge and without advertising.Donate here A normal inflammatory response in the human body is characterised by a temporary increase in inflammatory activity when there is a threat, which resolves once the threat has passed. Conversely, when we regularly adopt unhealthy eating habits, we suffer from low-grade chronic systemic inflammation, which ultimately causes significant alterations in all tissues and organs and, ultimately, increases the risk of developing various non-communicable diseases.The likelihood of developing depression doubles To confirm whether there is a direct link between adherence to a pro-inflammatory dietary pattern and the risk of developing depression, we conducted a longitudinal study of 3,206 Spanish adults who did not have depression at the start of the study, assessing the influence of diet during a three-year follow-up period. We calculated the inflammatory potential of the diet using the Inflammatory Diet Index, a scoring algorithm based on the impact of different dietary parameters (foods, nutrients and other bioactive compounds) on six inflammatory biomarkers (C-reactive protein, interleukin-6, interleukin-1β, interleukin-4, interleukin-10 and tumour necrosis factor-α).

We were thus able to determine that those who adhered to a pro-inflammatory diet based on high consumption of carbohydrates, trans fats, saturated fats and cholesterol reported a higher incidence of depression throughout the study follow-up. Specifically, participants with the highest inflammatory diet were twice as likely to develop depression as participants with an anti-inflammatory diet based on regular consumption of different nutrients and bioactive components such as dietary fibre, vitamins A, D and E, omega-3 fatty acids, beta-carotene, zinc, magnesium and selenium. All of these dietary parameters are present in foods such as fruits, vegetables, legumes, peas, nuts, fish, seafood and whole grains, among others. While further research is needed throughout adulthood to establish more solid conclusions, these results indicate that dietary habits can significantly influence the mental health of older adults. We would do well to start considering diet as a modifiable factor that could have a positive impact on the prevention of depression.

dietnutrition

depressioninflammation

Mediterranean diet

ultra-processed foods