How Is Omega 3 Used In The Body For Nutrition?

Omega-3 fatty acids are polyunsaturated fats which cannot be produced in the body from non-omega-3 sources. Nutritionally important omega-3 fatty acids include alpha-linolenic acid, ALA, eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA. Sources of ALA include flaxseeds, hemp seeds and walnuts while EPA and DHA are found in oily fish and fish oils. Omega-3 fatty acids are associated with a range of health benefits.

Conversion of ALA to EPA and DHA

ALA is the parent omega-3 and the body can elongate it into other omega-3s, including EPA and DHA, according to need. However, efficiency of this conversion is believed to be low: According to the DHA-EPA Omega-3 Institute, less than 8 percent of ALA is converted into EPA and for DHA, efficiency of conversion is lower than 4 percent. However, wide individual variations have been observed and women of reproductive age tend to have higher efficiencies than men.

Brain

EPA and DHA play important roles in the development and maintenance of the central nervous system and DHA is a major structural component of the brain. A recent evidence report by Dr. Catherine H MacLean, PhD, and colleagues, documents that deficiencies of omega-3s may be responsible for a variety of disorders affecting the central nervous system, including Alzheimer's disease, Zellweger's syndrome, Parkinson's disease and several psychiatric disorders.

Cardiovascular Disease

A review in the "Journal of the American Medical Association," reports that modest consumption of omega-3-rich fish reduces risk of coronary death by 36 percent and total mortality by 17 percent. Mechanisms for this protective effect include a reduction in triglyceride levels, an increase in the HDL, or good, cholesterol and an anticoagulant effect.

Inflammation

Omega-3 fatty acids have powerful anti-inflammatory properties by inhibiting the production of pro-inflammatory molecules. Thus omega-3s are important in conditions such as arthritis, which are characterized by excess inflammation, as explained by M. James and colleagues at the Rheumatology Unit at the Royal Adelaide Hospital.

Cancer

Omega-3s have been reported to protect against cancer. The August 1995 issue of the "European Journal of Cancer Prevention" reported that omega-3 consumption was associated with lower colorectal cancer mortality rates in men. The "British Journal of Nutrition" also reported that oral omega-3 supplementation is beneficial to cancer patients by improving their appetite and weight, their quality of life and reduced post-surgical morbidity.