Omega-3 fatty acids are a family of unsaturated fatty acids commonly found in fish oil and certain plant or nut oils Over the past several years, a number have studies have suggested that omega-3 fatty acid supplementation can lower blood pressure and reduce the risk of heart attack and stroke in people with known heart disease. However, this benefit is controversial because other studies have failed to show a significant protective effect against cardiovascular disease. Omega-3 fatty acids have also been studied for the prevention of Parkinson's disease and the treatment of depression and anxiety.

In the June 2008 issue of the Archives of Ophthalmology, researchers from Australia reported that eating fish and other foods rich in omega-3 fatty acids was associated with a reduced risk for age-related macular degeneration (AMD), a disease associated with aging that causes loss of sharp vision. AMD is the leading cause of vision loss in Americans who are 60 years of age and older. The researchers analyzed data from nine studies involving a total of 88,974 people, including 3203 people with AMD. They found that a high dietary intake of omega-3 fatty acids and eating fish at least twice a week were associated with a significantly reduced risk for AMD.

Although this report is compelling, the authors warn that there is not enough evidence to support routine consumption of omega-3 fatty acids for AMD prevention. Randomized clinical trials and prospective studies are still needed to bolster the findings of this study.