• 01 Jul, 2024
• Elizabeth Naraine

5 Science-Backed Ways Nutrition Impacts Your Mental Health

In recent years, the stigma surrounding mental health has improved significantly, and more people are now seeking help through therapy, medication, and alternative methods to treat mental health issues. As a result, there is a growing interest in the correlation between mental health and diet. The food you consume and your lifestyle are crucial to your overall well-being. Therefore, researchers have conducted studies to determine which foods, vitamins, and compounds can positively impact mood.

In this article, we will explain the science-backed ways nutrition can affect your mental health and explore the best diet to improve your overall well-being.

Omega-3 Fatty Acids May Treat ADHD

Omega-3 fatty acids, typically known as “healthy fats,” are found in many foods. These fats contribute to essential processes in the body, including neurotransmission, which involves the release of neuronal signaling molecules to other cells in the central nervous system. These signaling molecules are called neurotransmitters. Varying levels of neurotransmitter production have a direct influence on mood. For instance, dopamine is responsible for feelings of happiness and pleasure. Abnormal levels of neurotransmitters can lead to several disorders, including ADHD, characterized by inattention and impulsivity.

Recent research has focused on the balance between omega-6 and omega-3 fatty acids, which may affect mental health. The typical Western diet is relatively high in omega-6 fatty acids, which are found in foods like corn oil and soy oil. This high consumption of omega-6 fatty acids can create an imbalance between omega-6 and omega-3 fats in the body, which can lead to various health issues, including ADHD and major depressive disorder. The modulation of neurotransmission production by these fatty acids may be the reason behind these health issues.

On the other hand, omega-3 fatty acids have been found to positively impact the levels of dopamine and serotonin, two critical neurotransmitters in the brain. A diet rich in omega-3 fatty acids can help rebalance the body by restoring the equilibrium between omega-6 and omega-3 fats, thus contributing to overall health and wellness.

There are several food sources that are rich in omega-3 fatty acids, such as fatty fish like mackerel and salmon, as well as seeds like flax seeds and walnuts. Although eggs and dairy products from grass-fed animals also contain omega-3 fatty acids, the quantity is relatively smaller. Research suggests that supplementation of omega-3 fatty acids can help alleviate ADHD.

In a study involving almost 700 children, supplementing with omega-3 fatty acids resulted in a slight improvement in ADHD symptoms without any significant side effects. This treatment could be an excellent option for individuals seeking alternative treatments to pharmaceutical drugs or to enhance the effectiveness of traditional therapies.

Inflammatory Foods Increase Risk of Depression

Inflammation is the body’s response to harmful substances, such as bacteria and damaged cells. This process is part of the immune system’s defense mechanism, which helps in fighting infection and repairing tissue. The symptoms of inflammation include pain, redness, irritation, and swelling at the site of the inflammatory response. Sometimes, prolonged inflammation can lead to chronic diseases, including cardiovascular issues and cancer.

Interestingly, research has shown that stress and depression may be linked to chronic inflammation. The hypothalamic-pituitary axis (HPA) may play a role in this connection. The HPA controls the production of cortisol, known as the stress hormone. Studies have found that increased levels of inflammatory cytokines, such as TNF-α, can activate the HPA axis and increase cortisol secretion. Elevated cortisol and excess inflammatory molecules can adversely affect specific brain structures, including the amygdala and hippocampus. In fact, many individuals with major depressive disorder have increased levels of inflammatory markers, including IL-6 and IL-12, as well as increased cortisol levels.

Diet plays an integral role in the body’s inflammatory response. Various foods can induce inflammation, while others can have an anti-inflammatory effect. Foods high in saturated fats, sugar, and processed meats activate the body’s inflammatory response. They are also correlated with other conditions, including diabetes and neurocognitive disorders. Therefore, a diet with lower levels of these trigger foods may have a positive effect on depression. Along the same lines, a diet high in anti-inflammatory foods like green leafy vegetables and fruits may also help reduce inflammation in the body and potentially improve depressive symptoms.

In one study, 631 participants logged their diet according to the empirical dietary inflammatory index (EDII). The EDII looks at the weekly intake of pro- and anti-inflammatory food groups. The study found that an increase in pro-inflammatory food intake correlated with an increase in depressive symptoms, which was collected through a nine-item questionnaire to diagnose the severity of depression. These results suggest that consuming a diet with a lower EDII score, i.e., a diet with more anti-inflammatory foods, may help reduce the risk of depression.

B Vitamins Regulate Neurotransmitter Synthesis

There are 8 water-soluble B vitamins critical to various processes in the body, including riboflavin, niacin, folate, and more. Since the body does not retain B vitamins, they must be replaced daily through dietary sources. These vitamins act as coenzymes, facilitating chemical processes, including metabolism, energy production, and DNA repair. A deficiency in specific B vitamins may result in health issues, such as anemia, muscle weakness, and low energy. For example, low thiamine levels directly correlate with symptoms of fatigue and impaired reaction to stress.

B vitamins are involved in critical functions in the central nervous system. There are 3 main B vitamins that are considered neurotropic, including thiamine, pyridoxine, and cobalamin. For example, thiamine is essential to the synthesis of the neurotransmitter serotonin, while pyridoxine plays a role in creating multiple neurotransmitters, including serotonin and dopamine. Cobalamin supports nerve repair after an injury and synthesizes the insulating layer around nerves.

The neurotransmitter dopamine regulates feelings of motivation and satisfaction. When dopamine levels are balanced, individuals are more likely to experience a sense of ambition and accomplishment. On the other hand, serotonin contributes to emotional stability and a general sense of calm and well-being when present at normal levels in the brain. Since B vitamins contribute to the synthesis of these neurotransmitters, they indirectly impact mood, making it critical to maintain adequate levels of B vitamins through a balanced diet or supplements.

Plenty of foods contain B vitamins, including whole grains, eggs, meat, dairy products, and legumes. Foods like bread and pasta are typically fortified with B vitamins to improve their nutritional value. To ensure adequate consumption of all B vitamins, consume a diverse diet that includes a combination of these foods and fortified options, especially if you follow a vegetarian or vegan lifestyle where sources of B12 may be limited.

High Protein Foods Increase Dopamine and Serotonin Levels

Consuming high-protein foods can positively impact dopamine levels in the body. As mentioned previously, dopamine is a neurotransmitter that regulates mood, happiness, and the reward system. When protein is consumed, the body breaks down the protein molecules into smaller units called amino acids, which are subsequently absorbed by the cells to produce enzymes, repair tissues, and support various cellular functions. Inside neurons, enzymes facilitate the conversion of these precursor amino acids into neurotransmitters. Specifically, the production of dopamine requires the intake of certain amino acids, namely tyrosine and phenylalanine, found in protein-rich foods.

Adequate protein intake can also increase the levels of tryptophan in the body, the amino acid precursor for the production of serotonin. By optimizing serotonin levels, protein-rich diets may enhance the effectiveness of medications that modulate serotonin. For example, selective serotonin reuptake inhibitors (SSRIs) are a group of medications prescribed to treat depression and anxiety disorders. These drugs work by inhibiting the reabsorption of serotonin in the brain, therefore increasing serotonin levels between nerve cells. As a result, the availability of serotonin increases, which helps relieve symptoms associated with mental health issues.

Probiotics May Treat Major Depressive Disorder

Probiotics can regulate the microbiota in the gut. Research has revealed that individuals with major depressive disorder exhibit an imbalance in certain gut bacteria. In particular, they tend to have lower levels of Bifidobacterium and Lactobacillus and higher levels of Clostridium and Streptococcus, along with other types of bacteria. The list below outlines the ways in which probiotics might work to alleviate symptoms of depression:

1. Anti-inflammatory effects: Supplementation and dietary intake of probiotics may reduce the concentration of pro-inflammatory cytokines in the body.
   
   
2. Repair of gut permeability: Also known as “leaky gut,” this condition occurs when the small intestine becomes permeable to bacteria and toxins, increasing inflammation in the body. Probiotics work to repair the intestinal wall.
   
   
3. Modulation of neurotransmitter production: Probiotic treatment has been shown to restore normal levels of neurotransmitters, including serotonin, which can regulate mood and behaviour.
   

Foods rich in probiotics consist of yogurt, sauerkraut, and kombucha. In addition, you can take supplements with different strains to restore gut health. It is worth noting that while pre-clinical studies show a potential link between probiotics and mental health, further research is required to establish a definite connection.

What’s the Best Diet for Optimal Mental Health?

Numerous studies have been conducted to identify the most beneficial diet for maintaining good mental health. The main recommendation remains the Mediterranean diet. This diet contains food recommendations typically consumed by individuals who reside in areas bordering the Mediterranean Sea, including France and Greece. Here are some of the primary food options included in this diet:

The Mediterranean diet encourages a low intake of sweets and processed foods. High sugar consumption has been linked to several adverse health effects, including diabetes, obesity, and poor mental health. Frequent sugar intake leads to a chronic increase in insulin production, which can cause spikes in blood sugar levels. This process can lead to cellular aging, inflammation, and overall stress on the body, ultimately contributing to mental health concerns.

Processed foods can contain many additives and synthetic flavors that can lead to increased inflammation in the body and negatively affect emotional well-being. These additives can include artificial sweeteners, high fructose corn syrup, and other chemicals that can trigger a cascade of inflammatory responses.

While there is no one-size-fits-all diet that is perfect for everyone, it is generally recommended that individuals consume a diet that contains a good amount of fruits and vegetables. These foods are abundant in antioxidants, minerals, vitamins, and anti-inflammatory compounds, which can reduce inflammation in the body and have a positive effect on mental health.

Maintaining a moderate sugar intake rather than completely restricting it is also essential to promote a healthy relationship with food. Overall, focus on the consumption of whole, unprocessed foods, including vegetables, whole grains, fruits, and high-quality proteins, to maintain overall health and well-being.

Reference:

Belliveau, R., Horton, S., Hereford, C. et al. Pro-inflammatory diet and depressive symptoms in the healthcare setting. BMC Psychiatry 22, 125 (2022).

Bloch, M. H., & Qawasmi, A. (2011). Omega-3 fatty acid supplementation for the treatment of children with attention-deficit/hyperactivity disorder symptomatology: systematic review and meta-analysis. Journal of the American Academy of Child and Adolescent Psychiatry, 50(10), 991–1000. https://doi.org/10.1016/j.jaac.2011.06.008

Calderón-Ospina, C. A., & Nava-Mesa, M. O. (2020). B Vitamins in the nervous system: Current knowledge of the biochemical modes of action and synergies of thiamine, pyridoxine, and cobalamin. CNS neuroscience & therapeutics, 26(1), 5–13. https://doi.org/10.1111/cns.13207

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Journel, M., Chaumontet, C., Darcel, N., Fromentin, G., & Tomé, D. (2012). Brain responses to high-protein diets. Advances in nutrition (Bethesda, Md.), 3(3), 322–329. https://doi.org/10.3945/an.112.002071

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