Omega-3 fatty acids are polyunsaturated fats. There are three main omega-3 fats, eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA). Not all omega-3 fatty acids act the same way in the body. ALA is necessary for normal growth and development, a healthy nervous system, and enhanced skin health. But both EPA and DHA play an important role in heart health.

The body is capable of making EPA and DHA from ALA, but the conversion rate is relatively low, so it’s usually consumed from fish or seafood. DHA is especially important for brain development during gestation and early childhood. It’s found in high levels in the brain and in the cells of the retina, the part of the eye that registers images and transmits them to the brain for processing.