Justin Dobson, Ph.D(c), CSCS, SCCC
Inflammation is a natural response to stress put on the body. It is the first step in the body’s healing process, in which repair cells are directed from the blood into the injured tissue. Acute (short-lived) inflammation is necessary, but problems arise when inflammation persists (chronic inflammation). Besides rheumatoid arthritis or tendonitis, chronic inflammation accompanies many other disease states, such as atherosclerosis, coronary heart disease, diabetes, obesity, and certain forms of cancer.
Diet is one factor that influences inflammation status. Polyunsaturated fatty acids (PUFAs) - often deemed “good” fat - have profound impacts on cardiovascular disease. Of the known PUFAs, omega-6 and omega-3 fatty acids heavily affect inflammation. Omega-6 fatty acids are considered “pro-inflammatory” and, with increased dietary consumption, correlate with increased chronic inflammation. Although they help short-term repair in the body, their prolonged presence is known to be harmful. On the other hand, the inflammatory effects of omega-3 fatty acids are weaker and actually promote anti-inflammatory compounds throughout the body that prevent long-term damage from inflammation. The three main omega-3 PUFAs are alpha-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid (DHA). Researchers have suggested that healthy diets should have a 1:1 or 1:2 ratio of omega-3 to omega-6, but ratios commonly seen in the US typically vary within a 1:6 to a 1:20 range. Japan’s normal diets include a higher fish intake, resulting in a lower ratio (1:1 to 1:3). The key to improving US PUFA ratios is to balance the effects of pro-inflammatory compounds and anti-inflammatory compounds to produce and direct the repair cells only as needed. One method is through more informed dietary choices.
Livestock diets for cattle have changed, causing a shift from omega-3 rich meat to that of omega-6 but the food industry is compensating. Supermarkets now carry omega-3 enriched eggs and cereal, as well as DHA-enriched milk. Some lesser known sources include walnuts, kale, soy beans, Brussels sprouts, collard greens, winter squash, and tofu. The most obvious sources of omega-3 fatty acids are from flax seed, salmon, Halibut, and other cold water fish, or direct fish oil supplementation. To avoid concern about mercury and other metal levels found in fish, algal (water algae)-based oil supplements come in purified forms.
There are a number of purported benefits for increasing dietary omega-3 fatty acids. An excellent 2009 review by Riediger et.al in the American Dietetic Association outlines the benefits of omega-3 fatty acids for a healthy lifestyle. The use of fish oil, DHA, EPA, or ALA is discussed with potential effects on infant growth, cardiovascular disease, cancer, depression, dementia, Alzheimer’s, and ADHD. These are but a few areas that have been explored, and there will surely be more research in the future with omega-3 to combat some of the disease states that involve whole-body inflammation. For recommendations on dosing, check the National Institutes of Health website under the Office of Dietary supplements (link listed below).
Acute inflammation is necessary for good health, but only for a few days at most. Chronic inflammation that lasts several months or years is harmful. With poor eating habits and inactivity becoming more prominent in our society, it is suggested that chronic inflammation, based on omega-6 PUFAs, is currently causing or worsening health problems. Besides a healthy diet and routine physical activity, fish oil supplementation appears to be a critical step toward stopping chronic inflammation.
For further reading related to this topic:
- Natalie D. Riediger, Rgia A. Othman, Miyoung Suh, Mohammed H. Moghadasian, A Systemic Review of the Roles of n-3 Fatty Acids in Health and Disease, Journal of the American Dietetic Association, Volume 109, Issue 4, April 2009, Pages 668-679.
- NIH: Office of Dietary Supplements http://ods.od.nih.gov/factsheets/omega3fattyacidsandhealth/