What Are Omega-3s? Omega-3 fatty acids are essential fats that play important roles in brain function, heart health, inflammation regulation, nervous system function, and overall cellular health. Because the body cannot efficiently produce them on its own, they must come from food or supplementation. The three main forms of omega-3s are: EPA (eicosapentaenoic acid) DHA (docosahexaenoic acid) ALA (alpha-linolenic acid) EPA and DHA are the forms most commonly associated with re