The association between what we eat and our mental health is growing--adding to the evidence that diet can play a key role in preventing depression.

The most recent data comes from a study that compared the long-term effects of very low-carbohydrate and low-fat diets on mood and cognitive function. Earlier studies had shown little, if any, difference, at least in the short term. In this study, however, the researchers found that after one year, the low-fat diet produced favorable effects on mood and affect in overweight and obese people. These results were not seen in the people who consumed low-carbohydrate diets.

Although this is just one study and the results cannot be definitely applied across the population, the results have several implications for preventing or reducing  symptoms depression. First, rates of obesity are twice as high in people who suffer from depression. These individuals are more likely to be sedentary and to overeat, especially foods that are high in fats and sugars, which contribute to weight gain. So losing weight may reduce symptoms of depression in obese individuals--if they consume a diet that is low in saturated fats and sugar.

Furthermore, our body and our brain need adequate nutrients and vitamins to function properly. People who suffer from depression are more likely to be deficient in key nutrients, such as folic acid, omega-3 fatty acids, essential fatty acids, and vitamins B1, B6 and C. They are also more likely not consuming sufficient polyunsaturated fats and antioxidants (which are good for us). Therefore, antidepressants are less likely to be effective in depressed individuals with poor diets.

Research studies have shown that diets that are rich in processed foods--dairy, fried foods, refined and sugary foods--are also linked to increase risk of depression. In comparison, people who consume a diet rich in fish, fruits, and vegetables-the typical Mediterranean diet-have as much as a 30 percent lower risk for depression.

Well-balanced, healthy diets improve brain function, help us be more resilient in difficult situations, control stress, and help us overcome personality shortcomings. Experts are quick to point out that there is no one or two foods that make a difference. The dietary benefit comes from the cumulative and synergistic affect of all the nutrients we eat, not just individual foods.

If you are overweight and suffer from depression, you will likely find that losing weight by following a diet high in fruits, vegetables, fish, and legumes may help relieve your depression.

Sources

Brinkworth, Grant D., Ph.D., Buckley, Jonathan D., Ph.D., Noakes, Manny, Ph.D., Clifton, Peter M., Ph.D., and Wilson, Carlene J., Ph.D. "Long-term Effects of a Very Low-Carbohydrate Diet and a Low-Fat Diet on Mood and Cognitive Function." Archives of Internal Medicine 169 (No. 20) (2009). Web. 9 November. 2009

http://archinte.ama-assn.org/cgi/reprint/169/20/1873.pdf

"What is the role of Diet in Depression?" DepressionGuide.com. Web.

http://www.depression-guide.com/diet-depression.htm

Marano, Hara Estroff. "A diet low in fat and cholesterol may put you at risk for depression." Psychology Today, April 29, 2003. Web. 13 August 2007.

http://www.psychologytoday.com/articles/200304/the-risks-low-fat-diets

Anderson, Pauline. "Diet Rich in Processed Food Linked to Increased Risk for Depression." British Journal of Psychiatry 195 (2009): 408-413. Medscape Medical News. Web. 11 May 2009.

http://www.medscape.com/viewarticle/711867

Kelly, Janis C. "Mediterranean Diet May Cut Depression Risk." Archives of General Psychiatry 66 (2009): 1090-1098. Medscape Medical News. Web.

http://www.medscape.com/viewarticle/710145