Diet and Depression What's The Connection?

 Depression is a mental disorder and the leading cause of disability worldwide, according to the WHO. It is estimated that 5% of adults worldwide suffer from it. 1 Furthermore, various studies suggest that diet may influence the pathology of the disease. First, inflammation plays an important role in depression, as during the inflammatory response, mediating molecules are produced that influence brain activity and the regulation of emotions. 2 In fact, different foods in the diet can influence the inflammatory process.

The Nurses' Health Study found that people who ate a lot of vegetables, fruits, whole grains, fish, and legumes tended to have lower levels of inflammatory markers in their blood. In contrast, those who followed a Western-style diet—eating a lot of red and processed meats, refined carbs, and processed foods—tended to have higher levels of these markers. When it comes to oxidative stress, researchers have shown that it plays a significant role in the disease because the brain is especially vulnerable to oxidative damage.

Implications for Diet and Future Directions for Nutritional Psychiatry

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Specifically, a meta-analysis of 115 studies concluded that people with depression had high levels of oxidative stress markers. Diet can also improve oxidative stress through the consumption of foods with antioxidant properties. For example, fruits and vegetables, olive oil, and nuts, which contain vitamins C and E, have antioxidant power. Similarly, polyphenols found in herbs, spices, berries, green tea, nuts, red wine, and other plant-based foods also have antioxidant properties.

Regarding the gut microbiota, it is one of the first systems in the body to interact with the foods we eat. It also regulates various mechanisms involved in depression, such as inflammation. Therefore, various animal studies suggest that the microbiota may serve as a link between diet and brain health. Consequently, various studies suggest that the intake of probiotics and prebiotics can improve gut health, reducing inflammation and depression.

How can food boost your mood?

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On the other hand, between 2014 and 2018, researchers conducted a study called MooDFOOD in 9 European countries to investigate how food intake, nutrients, eating behaviors, and obesity relate to the development of depression. 6 The main conclusions reached were: Regarding the prevention of depression, following a healthy dietary pattern characterized by a high consumption of fruits and vegetables, plenty of legumes, weekly fish intake, choosing whole grains, moderate consumption of dairy products, chicken, eggs, and nuts, and low consumption of red and processed meats and alcohol can reduce symptoms of depression in the general population.

Likewise, weight loss in obese people helps reduce the symptoms of depression. 7 Regarding the treatment of depression, following a healthy dietary pattern can help reduce symptoms of depression in patients with Major Depressive Disorder (MDD). Furthermore, omega-3 supplements (>= 1 g/day of EPA and DHA) may have a small beneficial effect on depression symptoms in people with MDD who take antidepressants. Depression is one of the leading causes of disability worldwide, and scientific evidence suggests that a healthy diet can help prevent the symptoms of the disease.

Broad Classes of Nutrition Influence Depression Risk

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However, we must emphasize that a healthy diet cannot replace the medical treatment needed to heal depression. Depression occurs because of imbalances in neurotransmitters such as serotonin, dopamine, norepinephrine, and GABA. As many studies confirm, the amino acids tryptophan, tyrosine, phenylalanine, and methionine are useful in treating mood disorders such as depression. Tryptophan, a precursor of serotonin, can induce sleep and reduce anxiety.

Tyrosine and its precursor, phenylalanine, are converted into dopamine and norepinephrine, increasing alertness and energy levels. The most common nutritional deficiencies observed in patients with mental disorders are amino acids (which are the precursors of neurotransmitters), omega-3 fatty acids, B vitamins, and minerals. The body builds proteins from amino acids. Out of the 20 amino acids available, the body naturally produces 12 of them, while the remaining 8 — known as essential amino acids — must come from the diet. A diet with high-quality protein would include meat, dairy products, and eggs. If there is insufficient intake of these amino acids,

Conclusion

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Mood food analyzed the links between the two disorders to ask whether improving behavior related to diet and nutrient intake could help prevent depression, specifically in people prone to being overweight. Based on a large number of studies and detailed analysis, the researchers reached three conclusions first, a healthy diet rich in fruits, vegetables, whole grains, fish, legumes, and olive oil, and low in red meat and full fat dairy products may reduce the risk of developing depression second, in obese people, weight loss may be accompanied by a reduction in depressive symptoms and third, current evidence does not support the use of nutritional supplements to prevent depression.

After a review of the scientific literature, MooDFOOD researchers developed a theoretical model to highlight which relationships between diet and depression merited further investigation. The model also incorporated the influence of lifestyle, environment, and psychology. We started with observational studies linking nutritional intake and eating behavior with depressive symptoms and vice versa. We also reviewed studies that had examined the effect of specific nutrients on depression or depressive symptoms,” says Professor Ingeborg Brouwer.