The Effect of Diet on Mental Health

The brain controls and regulates most of the vital functions of the body, consciously or not. For this reason, it is essential that the brain receives a constant supply of fuel and oxygen. Fuel is obtained by metabolizing available nutrients in the bloodstream, which originate from digested food.

The brain consumes 20% of the daily calorie intake, that is about 400 (out of 2000) calories per day. Structurally, about 60% of the brain is fat, which consists of high cholesterol and polyunsaturated fatty acids (PUFAs).

Therefore, the food one eats is directly related to the structure and function of the brain and thus affects the functioning of the mind. Many studies have found that diets that are too high in refined sugars are toxic to brain function because the high content of simple sugars stresses the pancreas and induces insulin resistance. High blood sugar levels with compensatory insulin responses stimulate the counter-reactive surge of autonomic neurotransmitters such as cortisol and glucagon.

These are known to produce increased anxiety, hunger, and irritability. In addition, they induce inflammatory and oxidative stress. This has been linked to an exacerbation of symptoms of depression and other mood disorders. These findings have led to the emerging field of nutrition. psychiatry that tracks the relationships between food, feelings, the gut microbiota, and human behavior.

Deficiency and mood disorders

Deficiency of nutrients such as cobalamin, folate, and zinc are known to be associated with symptoms of depression and dementia, cognitive decline, and irritability. Both overeating and food insecurity are associated with mood and anxiety disorders.

Mental illnesses are among the largest contributors to the global health burden, especially depression, which accounts for the majority of disability in most developed countries, especially in the 15-44 age group. Therefore, it is crucial to explore nutritional strategies to improve these conditions.

Not only do people eat differently when they’re anxious or depressed, but these changes can go in either direction. Rather, depression can be the result, at least in part, of poor eating habits, or it can be made worse by the patient’s inability to stop eating comfort foods and choose a healthy diet. Such disability may be financial, psychological, or iatrogenic.

Serotonin and the gut

Serotonin is a monoamine neurotransmitter that helps control sleep and appetite, inhibit pain, and regulate mood. About 95% of serotonin is produced in the intestine, which is rich in neurons: the enteric plexus contains a hundred million nerve cells. Therefore, the gut is intimately involved in emotional regulation, pain perception, and vital physiological functions.

Interestingly, the function of these neurons and their secretion of serotonin and other neurotransmitters is tightly regulated by the metabolic byproducts of the trillion bacteria that make up the gut microbiome. These bacteria ensure the integrity of the epithelial barrier of the intestine, preventing the entry of bacterial toxins and pathogens into the systemic circulation. They also prevent the spread of inflammation beyond the intestinal lumen, improve nutrient absorption, and activate the gut-brain neural pathways – the gut-brain axis.

Monoamine neurotransmitters are synthesized from amino acids in a process mediated by mineral-dependent cofactors. Both folate and vitamin B12 are essential for the methylation that occurs during these synthetic processes, and they also regulate the formation of homocysteine, a metabolite strongly related to cardiovascular risk and depression.

Dietary fats and brain function

Anti-inflammatory fats, such as omega-3 fatty acids (FAs), are known to be essential components of neuronal cell membranes and also play a role in many vital neuronal processes, including neurotransmission, gene expression, neurogenesis, and neuronal survival. They are also known to have antioxidant properties.

Omega-3 fatty acids are used to treat a number of psychological disorders, including attention deficit hyperactivity disorder (ADHD), depression, bipolar depression, and post-traumatic stress disorder (PTSD). A high proportion of omega-6 is related to a higher incidence of these conditions, especially the first two.

The standard Western diet is high in omega-6 but low in omega-3 fatty acids, primarily due to consumption of refined sugars and flours, highly processed foods, and low amounts of seafood (including fish) and beef fed with pasture.

Some studies have confirmed that diets that are higher in carbohydrates and healthy fats, and lower in refined and highly processed foods, such as the Japanese and Mediterranean diets, are linked to a reduction in the incidence of depression by between a quarter and more of a quarter. third, compared to the standard American diet.

Inflammation and diet.

Inflammation of the nervous system is also important in the pathogenesis of mental illness, and this is also related to diet. Many biomarkers of inflammation, such as C-reactive protein (CRP) and tumor necrosis factor alpha (TNF-α), were associated with a dietary pattern that was linked to an increased risk of depression over the next decade or so. This pattern included high simple sugars (sugary beverages and refined flours), red meat and margarine (saturated fats), and few green or yellow vegetables, coffee, wine, or olive oil, which are characteristics of the stereotypical Western diet.

The high content of vegetables, fruits, grains, and seafood, with less dairy and meat content, and no refined foods, of the Mediterranean and Japanese diets compare very favorably with the Western diet. The former uses small amounts of red wine and cheese or yogurt in the daily diet. The mechanism is thought to be through brain-derived neurotrophic factor, or BDNF.

This important molecule is involved in the plasticity and survival of neurons and neurogenesis. It is reduced in many mental health conditions, such as depression, PTSD, and schizophrenia, and is affected by many commonly prescribed antidepressants.

Not only that, but the former features many of the fruits and vegetables in a fermented form, providing probiotics that protect the gut by improving the content of health-promoting gut microbes and reducing or preventing inflammation throughout the body.

Therefore, including more foods with omega-3 fatty acids in the diet when taking medications that induce inflammation not only prevents inflammatory changes but also prevents the induction of depression in such individuals, according to recent work, certainly early . Again, the Mediterranean diet promotes gut microbes that produce anti-inflammatory metabolites.

Of course, depressive tendencies or stressors can prevent the beneficial effects of healthy foods from manifesting as reduced inflammation or improved mood. Second, only some depressed people show this inflammatory tendency, which may mean that diet plays this role in only a proportion of people, perhaps with other inflammatory conditions or due to constitutional factors.

conclusion

Many experts would recommend that people pay attention to the relationship between their diet and the foods they eat for a month or at least two weeks. If they could reduce or eliminate processed foods and sugars during this time period, before bringing these foods back one by one, it would be instructive to notice how they feel.

Better eating strategies are essential to promoting mental health and recovery from mental illness. More than 2,000 years ago, the famous Greek physician Hippocrates said: “May your food be your medicine and your medicine be your food.”

The Mediterranean diet (and the like) not only affects the availability of brain building blocks and neurotransmitters, including myelin, neuronal membrane, and monoamine neurotransmitters, it modulates key chemicals like BDNF to alter neuroplasticity, silences the inflammation of the system, and determines the health and status of the gut microbiome.

Many of these traditional diets are known to include mostly nutritious whole foods without much processing. The role of a dietitian in helping patients with mental health problems choose approaches that promote self-care and improved health is very important and should be encouraged.

As one group of authors comments,

This message supports the idea that creating environments and developing measures that promote healthy and nutritious diets, while reducing the consumption of highly processed and refined “junk” foods, can provide benefits even beyond well-known effects on physical health, including improved psychological well-being..”

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