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FOODS FOR DEPRESSION

Whether due to genetics, a life experience, an illness or stress, depression can be extremely debilitating for those who develop it. Food is an integral part of maintaining a continuous supply of nutrients essential for keeping your brain chemically balanced. There are a number of ways in which to treat depression including medication, lifestyle changes, activity, food and nutrition. Nutrition is an important place to start for managing depressive symptoms, because it is natural with limited side effects and can be a long-term positive change for the individual. 

Carbohydrates

There are many different hormones, neurotransmitters and other substances that play a role in how we feel, act and react. One chemical that has received a great deal of press for its ability to affect mood, is the monoamine Serotonin. Serotonin is formed in the brain and can be found in three parts of the body, the brain, the lining of the digestive tract and blood platelets. Its roles include improving mood, giving a satisfied feeling from food and promoting sleep and relaxation. Depression has been linked to reduced quantities or activity of the neurotransmitter serotonin in the brain. Medications, called ‘selective serotonin re-uptake inhibitors (SSRI), essentially work to balance the levels of serotonin.  Alternatively, food can also affect serotonin levels, namely carbohydrate rich meals.  Carbohydrates can increase blood levels of the amino acid tryptophan that essentially acts as a precursor to serotonin. One can experience significantly increased levels of serotonin only minutes after eating carbohydrate foods.

However, not all carbohydrates sources are great for maintaining optimal serotonin levels. Carbohydrates with lower glycemic indexes (GI) (eg. Fruit, vegetables, whole grain breads, All Bran cereal) contain lots of fibre and are slower carbohydrates than foods with a high Glycemic Index (eg. table sugar, candy, sodas, refined bread products). The low GI foods are digested and absorbed as sugar into the blood stream at a slower rate than the high GI foods and therefore last longer and provide a more constant supply of fuel, carbohydrate and tryptophan to the brain.  Hence a more stable supply of serotonin.  Alternatively, faster carbohydrates with high GI values are released into the blood stream quickly allowing the blood sugar to rise with an initial burst of tryotophan (and thus serotonin) and then crash as the body burns the simple sugars rapidly. This can cause a hypoglycemic effect, causing both sugar levels and serotonin levels to fall which can contribute to depression. By balancing your meals with low GI foods at each meal one can create a steady flow of tryptophan for producing serotonin.

Omega-3 Fatty Acids

A deficiency in essential fatty-acids has been linked to depression, anxiety, aggressiveness and insomnia. Some studies have even found that patients with depression have shown lower levels of omega-3 fatty acids in their cell membranes. Other research has found that an essential fatty-acid deficit can worsen attention deficit hyperactivity disorder (ADHD) significantly. Lastly, studies have also shown that there is a marked stabilizing effect on the mood in bipolar patients who consumed omega-3 fatty acid supplements.

Essential fatty-acids are fatty acids that the body can not manufacture itself, and thus must be ingested through dietary means. Some examples of omega 3 rich foods are fatty fish such as salmon and mackerel as well as ground flaxseeds, olive oil, walnuts, pumpkin seeds and specialty eggs from chickens that have been fed flaxseed in their feed.  Try sprinkling ground flaxseed on your favourite cereal or salad for a quick and easy way to boost omega-3 fatty acids.

Mind your B’s and C’s

Deficiencies of folate, vitamin B-12, vitamin B-6 and vitamin C have all been suggested to have links with depression.

Folate

In a study conducted by Nutrition Reviews in 1997, a relationship was found between a folate deficiency and neuropsychiatric disorders. In addition it was depression that seemed to be the primary manifestation of folate deficiency. Low serum or red blood cell folate levels were detected in 15-38% of the adults that were diagnosed with depression. Low folate levels may also reduce the body’s response to SSRI’s. Spinach, broccoli, tomato juice, kidney beans, lentils and asparagus are all high in folate. Be aware that heat can inactivate the vitamin and so by overcooking your folate rich sources of foods you may be decreasing your intake. 

Vitamin B-12

Vitamin B-12 is another B vitamin that has been linked to depressive symptoms.  B-12 is found predominantly in animal products, such as milk, meat, cheese and yogurt. Therefore, vegans and some vegetarians can be deficient in this crucial vitamin. In addition, elderly people may experience B12 malabsorption which can cause deficiency.  There is a long list of psychiatric illnesses or symptoms that have found to be attributed to vitamin B-12 deficiency including mood disorders, dementia, paranoid psychoses, violent behavior and fatigue. The easiest way in which to increase B12 is via consuming animal products or via B12 shots or injections. 

Vitamin B-6

Vitamin B-6 may also be effective in treating children who have low serotonin levels and Attention Deficit Hyperactivity Disorder (ADHD). However, the studies found that it does not appear to help kids with ADHD who do not have low serotonin levels. Vitamin B-6 is essential in the manufacturing all of the monoamines (eg. Serotonin, dopamine) from amino acids. Essentially, drugs prescribed for depression try to increase these monoamines in different ways.  However, by providing precursors for these monoamines through dietary means, it is possible to increase the monoamines to their optimal levels. Vitamin B6 can be found in protein rich foods such as poultry, fish and eggs. Other great sources include unprocessed rice, soybeans, oats, wheat products, lentils, peanuts and walnuts.

Vitamin C

Lastly, vitamin C has also been found to have an effect on depressive symptoms. Studies have indicated that deficiency can manifest in psychological signs including hysteria and depression. Vitamin C can easily be increased in the diet through regular fruit and vegetable intake. Oranges are very high in vitamin C, as are grapefruit, red bell peppers, kiwi’s, Brussels sprouts, spinach and broccoli. 

Avoid caffeine and alcohol

Foods that interfere with proper brain function include caffeine and alcohol. Caffeine is actually a stimulant that speeds up neurotransmission initially (raising the amount of serotonin and thus elevating mood), but results in increased anxiety and nervous muscle tension soon after its consumption. Regular alcohol consumption should also be avoided because it is a depressant and can contribute to depressive symptoms. It interferes with brain cell processes and disrupts sleep cycles. It can also exacerbate hypoglycemia, which is another cause of depression.

Balance

Ideally, the individual with depression wants to balance their diet focusing on whole, natural, unprocessed foods that are high in quality and nutrient density. A diet high in plant foods such as vegetables, fruits, grains, beans, seeds and nuts ensures that you are consuming carbohydrates, fiber, vitamins, minerals and antioxidants that can protect your body’s cells from damage. These foods are also important in raising serotonin levels in the brain. In addition, legumes, fish and other seafood (being rich in protein) are terrific foods for raising dopamine and norepinephrine levels. 

The Bottom Line:  Diet is key in reducing symptoms of depression and improving mood in a safe and effective way.  It may not be all that is required to manage depression so you should continue to follow the advice of your physician.