Omega-3: DHA and EPA
Dietary fat is an important source of energy and a necessary part of the human diet. Fatty acids, a component of fat molecules, are important in keeping our eyes healthy.
Two families of essential fatty acids exist in nature: omega-3 and omega-6. These essential fatty acids help support the cardiovascular, reproductive, immune and nervous systems. They also help the brain develop and the sensory systems mature.
Research has shown that two omega-3 fatty acids—docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)—are important for proper visual development and retinal function.
DHA is found in the highest concentration in the retina, suggesting it has an important function there. EPA is used in the production of DHA in the body.
Studies in pre-term and full-term infants suggest that getting enough omega-3 fatty acids in the diet is essential for optimal visual development. A number of studies have shown that animals that do not get enough DHA in their diets suffer visual impairment and degradation of the retina.
Dry eye syndrome also has been linked to omega-3 deficiency. Additionally, low levels of DHA and EPA have been associated with diabetic retinopathy, age-related macular degeneration (AMD) and retinopathy of prematurity.
The typical American diet includes 1.6 grams per day of omega-3 fatty acids. EPA and DHA usually comprise 6 percent to 12 percent of this value (0.1-0.2 grams per day). This level is well below the American Heart Association's recommended 0.5-1.0 grams per day of EPA + DHA. According to the U.S. Food and Drug Administration, consuming up to 3 grams per day of DHA and EPA is generally considered safe.
EPA and DHA are concentrated in fatty fish and other seafood. In addition, you can take omega-3 fatty acid supplements in oil or capsule form.
For individuals who choose not to consume fish, vegetarian DHA is commercially manufactured from microalgae.
Animals can convert very small amounts of DHA through consumption of α-linolenic acid, an omega-3 fatty acid found in plants, animals and milk.
*At this time, the AOA is unaware of any studies that have examined interactions between specific medications and essential fatty acids. The AOA also is not aware of any adverse health reports from interactions between specific medications and essential fatty acids. However, the AOA recommends consulting with a health care professional before taking any supplement.