Omega-3 fatty acids and depression
Several studies have suggested that decreased intake of omega-3 fatty acids may increase the risk of depression, and that supplementing the diet with omega-3 fatty acids may help alleviate symptoms of depression. Essential fatty acids may help restore normal levels of neurotransmitters such as serotonin, which are believed to be lower in people with depression, and may also increase levels of molecules that benefit the brain, such as brain-derived neurotrophic factor.
People with diabetes are at higher risk for depression, and depression tends to worsen diabetes control. For this reason, awareness of factors that may contribute to the development of depression is particularly important for people with diabetes. (Read more about depression and diabetes at www.diabetesselfmanagement.com/articles/Emotional_Health.)
Although DHA is the predominant omega-3 fatty acid found in the brain, EPA may be a more effective treatment for depression. Some studies have shown that either EPA with DHA or EPA alone is effective at treating depression, but that DHA alone is not. More studies still need to be done to determine which essential fatty acid or combination of essential fatty acids is best for treating depression. Studies also need to help determine what dose of essential fatty acids should be used and for how long.
When deciding whether to supplement your diet with omega-3 fatty acids, there are several things to consider. As usual, it is best to consult your physician or dietitian, since a medical professional who knows you can make the best recommendation based on your personal health, lifestyle, and diet.
If you decide to increase your fish consumption or to use fish oil supplements, select fish and supplements that contain the lowest obtainable levels of polychlorinated biphenyls (PCBs), mercury, and dioxins. These are waterborne pollutants found in fish that may have harmful effects if consumed. To learn more about mercury levels in commercial fish, visit this site provided by the U.S. Department of Health and Human Services and the U.S. Environmental Protection Agency: www.cfsan.fda.gov/~frf/sea-mehg.html. To find out more about fish oil supplements and suppliers that have been United States Pharmacopeia (USP) verified (certified to contain the level of active ingredient listed on the label), go to www.usp.org/USPVerified/dietarySupplements.
Flaxseed oil is another potent source of omega-3 fatty acids. It is rich in ALA, the precursor of DHA and EPA. Not all ALA ingested is converted by the body, however, and the ability to convert ALA into DHA and EPA may be impaired in people with diabetes. Despite these limitations, flaxseed may be a good option for people who do not want to consume fish products.
Fishing for good health
Although further research is needed to more fully understand how essential fatty acids work, current evidence suggests that almost everyone would be better off with increased consumption of omega-3. It is important to note that essential fatty acids are, in fact, fats, so take care not to increase total intake of fat or calories when adding them to your diet. In nearly all respects, however, foods and supplements that contain omega-3 fatty acids seem to be a good catch.