Depression is one of the most common psychological disorders today. It influences about 322 million people. The worldwide prevalence of depression in 2015 is estimated to be 4.4% by the World Health Organization (WHO) and it is seen more common among women (5.1%) than men (3.6%). Additionally, a study conducted in England showed that the incidence of depression in youth has increased for twice in 12 years (Holford, 2003) so depression is very important to be taken considered with all of its aspects.
The Symptoms of Depression
- Depressed mood
- Feeling sad and hopeless
- Losing interest in pleasurable activities
- Decreased self-worth
- Sleep problems
- Poor concentration
- Inadequate function at work/school, family, and social life
- Reduced self-care
- Loss of appetite, or eating too much and unhealthy
If you have these symptoms for more than 2 weeks, then you probably experience depression.
Even if depression is considered as psychological and biochemical, and suggested to treat it by counselling and taking antidepressants, it also has been evaluated with a new approach (Holford, 2003): Nutrition.
What Affects Us to Have a Tendency to Experience Depression?
- Blood glucose imbalance,
- Lack of amino acids (protein),
- Lack of essential fats like Omega-3,
- Lack of B-complex vitamins (especially B1 for women; B2, B6, and B12 for both),
- Low levels in minerals (Calcium, chromium, iodine, iron, lithium, selenium, zinc),
- Lack of carbohydrates,
- Lack of folate (also known as vitamin B9),
- Low levels of testosterone and oestrogen cause fatigue, irritability, poor concentration, mood changes and depression (Harbottle & Schonfelder, 2008; Holford, 2003; Shepherd, 2001; Rao, Ashal, Ramesh & Rao, 2008). In addition, while serotonin affects mood changes, dopamine, noradrenaline, and adrenalin affect motivation in people.
The Link between Depression and Nutrition
In a review study (Holford, 2003), it has indicated three points about the relationship between depression and nutrition. These are:
- It is found a link between the incremental incidence of depression and a significant decrease in the consumption of vegetable and fish, which contain folic acid and essential fats and an increase in sugar intake (from 2 lb in the 1940s to 150 lb). In the last 50 years, we have become to consume high energy but low nutritive valued and processed foods. Sugar and trans-saturated fats intake have drastically risen up and this unhealthy nutrition has costs for us, such as obesity, cardiac problems, depression and other mental health disorders (Peter, 2004; cited in Harbottle & Schonfelder, 2008).
- Since depression has a biochemical aspect, it is crucial to know how the brain uses nutrition ingredients to change back into the normal construct, which includes its own biochemistry.
- Today’s world and people are more stressful and live fast so the brain needs more energy, thereby more nutrition to feed itself.
Antidepressants are known as blockers for serotonin to reuptake, thereby, make the depressed people improve their depressed mood (because serotonin makes us feel happy and high). According to a study, women seem to predispose to have low serotonin level than men. While low serotonin level shows itself with depression and anxiety in women, it does with aggression and risky behaviours in men (Nishizawa et al., 1997).
Many of the food patterns before depression are actually the same when depression occurs, for instance, poor appetite, skipping meals, and desire for the foods that include sugar. So it is seen that people with depression usually don’t eat healthy and enough. They even choose the foods, which may cause an increase in depression level (Beardsley; Rao, Ashal, Ramesh & Rao, 2008).
See the Big Picture
We’ve seen in many studies that changing dietary behaviours and eating healthy foods with full of vitamins, minerals, proteins and other things our bodies need, will help us to improve our lower mood, anxiety, concentration, fatigue, and so many other things. If a person has an unhealthy diet, most probably he or she will continue these dietary behaviours during the depression because depression and nutrition are the two variables that trigger to each other and because the person loses self-care and decrease healthy diet and behaviours in depression. If we see the big picture, we can see that it is kind of a vicious cycle, and to break this cycle, it is crucial to give importance to our dietary behaviours and keeping away from unhealthy ones.
A Recommended Diet That Could be Helpful for You
Recommended diet (Harbottle & Schonfelder, 2008; Holford, 2003; McCulloch, 2018; Link, 2018):
- Reduce sugar intake and stimulants (drinks including caffeine, smoking, fizzy drinks).
- Reduce eating fast-foods and processed foods that contain trans-saturated fats.
- Eat oily fish, which is rich in Omega-3 at least twice a week.
- Increase eating vegetables and fruits.
- Take adequate amount of beans, meat, egg, and fish etc., which are rich in tryptophan (Serotonin is made by tryptophan).
- Take vitamin B (especially B1, B2, B6, and B12). They are included in salmon, leafy greens, liver and other organ meats, eggs, milk, beef, legumes, chicken, yogurt, trout and so on.
- Take iron supplements if you have anaemia (with the control of your doctor).
- Folate is important nutrients to improve depression in people. It is included in Brussels sprouts, broccoli, nuts and seeds, beef liver, wheat germ, bananas, avocado, spinach and so on.
As many specialists have carried out studies and reached a common conclusion, there is a strong link between depression and nutrition. When we eat unhealthy foods that lacking minerals, protein, carbohydrates, essential oils, vitamins, folate and containing too much sugar, trans-saturated fats, we improve a tendency to experience depression. Nutrition part was not considered important and didn’t take enough attention so far; however, today’s psychological science is aware of this aspect and how it actually has a big influence on people’s mental health.
While an unhealthy diet is one of the aetiologies of depression, also experiencing depression inclines to eat unhealthily. It is turning into a vicious cycle so the best thing we can do is be aware of the links between depression and nutrition, and make a healthy diet for us.
American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC.
Beardsley, B. Depression, and Nutrition.
Harbottle, L., & Schonfelder, N. (2008). Nutrition and depression: A review of the evidence. Journal of Mental Health, 17(6), 576-587.
Holford, P. (2003). Depression: The nutrition connection. Primary Care Mental Health, 1, 9-16.
Link, R. (2018, May 22). 15 Healthy Foods That Are High in Folate (Folic Acid).
McCulloch, M. (2018, October 11). 15 Healthy Foods High in B Vitamins.
Nishizawa, S., Benkelfat, C., Young, S. N., Leyton, M., Mzengeza, S., Montigny, C, Blier, P., & Diksic, M. (1997). Differences between males and females in rates of serotonin synthesis in human brain. Proc Natl Acad Sci, 94, 5308-5313.
Rao, T. S. S., Asha1, M. R., Ramesh B. N., & Rao, K. S. J. (2008). Understanding nutrition, depression, and mental illnesses. Indian J Psychiatry, 50, 77-82.
Shepherd, J. (2001). Effects of estrogen on cognition, mood and degenerative brain diseases. Journal of the American Pharmaceutical Association, 41, 221-228.
World Health Organization (2017). Depression and Other Common Mental Disorders: Global Health Estimates. Geneva.