The Link Between Depression and Nutrition
Although most people accept that certain foods increase physical stress on the body by making digestion more difficult, few realize that similar reactions can occur neurologically when certain eating propensities deny the brain essential nutrients. The connection between nutritional deficiencies and physical illness has been clearly illustrated in depression, which, until recently, has been more typically thought of as strictly biochemical-based or emotionally-rooted. On the contrary, nutrition can play a key role in the onset as well as severity and duration of depression.
The newly evolved discipline of nutritional neuroscience addresses how nutritional factors are intertwined with human cognition, behavior, and emotions. On the basis of accumulating scientific evidence, an effective therapeutic intervention has emerged, namely nutritional supplement/treatment. These may be appropriate for controlling and to some extent, preventing numerous mental/behavioral conditions, especially depression. Studies have indicated that daily supplements of vital nutrients are often effective in reducing symptoms.
Some aspects of nutrition that may be associated with depression include insufficient omega-3 fatty acids, vitamins C and E, as well as use of alcohol, caffeine, and an overall style of diet such as the “western” diet heavily containing processed foods, fried foods, refined grains, sugary products and beer. Many of the easily noticeable food patterns that precede depression are the same as those that occur during depression. These may include poor appetite, skipping meals, and a dominant desire for sweet foods. Numerous studies have shown that a dietary pattern characterized by vegetables, fruit, meat, fish, and whole grains is associated with lower risk of depression.
The most common nutritional deficiencies seen in patients with mental disorders are of omega–3 fatty acids, B vitamins, minerals, and amino acids that are precursors to neurotransmitters. The omega-3 fatty acids known as eicosapentaeoic acid (EPA) and docosahexaenoic acid (DHA) are the most common polyunsaturated fatty acids in the brain. They help regulate dopamine and serotonin levels, communication among brain cells, and brain glucose metabolism. Experts suggest that deficiencies of omega-3 fatty acids in the diet may affect depression because they are widespread in the brain, which is is one of the organs with the highest level of lipids (fats). Brain lipids, composed of fatty acids, are structural constituents of membranes. It has been estimated that gray matter contains 50% fatty acids that are polyunsaturated in nature (about 33% belong to the omega-3 family), and hence are supplied through diet. One to two grams of omega-3 fatty acids taken daily is the generally accepted dose for healthy individuals, but for patients with mental disorders, up to 9.6 g has been shown to be safe and effective.
Accumulating evidence from demographic studies indicates a link between high fish consumption and low incidence of mental disorders; this lower incidence rate being the direct result of omega–3 fatty acid intake. Omega-3 fatty acids are found in high concentrations in oily fish such as salmon, herring, mackerel, anchovies and sardines, as well as flax seeds and walnuts.
Supplements containing amino acids have also been found to alleviate depression and other mental health problems. Amino acids comprise proteins, which are important building blocks of life. As many as 12 amino acids are manufactured in the body itself and remaining eight (essential amino acids) have to be supplied through diet. A high quality protein diet contains all essential amino acids. Foods rich in high quality protein include meats, milk and other dairy products, and eggs. Plant proteins such as beans, peas, and grains may be low in one or two essential amino acids. Protein intake and in turn the individual amino acids can affect the brain functioning and mental health.
Many of the neurotransmitters in the brain are made from amino acids. The neurotransmitter dopamine is made from the amino acid tyrosine and the neurotransmitter serotonin is made from the tryptophan. If there is a lack of these two amino acids, there will not be enough synthesis of the respective neurotransmitters, which is associated with low mood and aggression in patients. The amino acids tryptophan, tyrosine, phenylalanine, and methionine are often helpful in treating many mood disorders. When consumed alone on an empty stomach, tryptophan, a precursor of serotonin, is usually converted to serotonin. Hence, tryptophan can induce sleep and tranquility. This implies restoring serotonin levels lead to diminished depression precipitated by serotonin deficiencies. Tyrosine and sometimes its precursor phenylalanine are converted into dopamine and norepinephrine.
Folate’s critical role in brain metabolic pathways has been well recognized by various researchers who have noted that depressive symptoms are the most common neuropsychiatric manifestation of folate deficiency. It is not clear yet whether poor nutrition, as a symptom of depression, causes folate deficiency or primary folate deficiency produces depression and its symptoms.
Randomized, controlled trials that involve folate and vitamin B12 suggest that patients treated with 0.8 mg of folic acid/day or 0.4 mg of vitamin B12 a day will exhibit decreased depression symptoms. In addition, the results of several case studies where patients were treated with 125-300 mg of magnesium (as glycinate or taurinate) with each meal and at bedtime led to rapid recovery from major depression. It has been observed that patients with depression have blood folate levels, which are, on an average, 25% lower than healthy controls. Low levels of folate have also been identified as a strong predisposing factor of poor outcome with antidepressant therapy. A controlled study has been reported to have shown that 500 mcg of folic acid enhanced the effectiveness of antidepressant medication.
Body RX Anti Aging offers nutritional consulting in regard to the relationship between depression and nutrition. Call us today to schedule an appointment 786-899-4514!