Overview

By Mayo Clinic Staff

Fish oil is a dietary source of omega-3 fatty acids. Your body needs omega-3 fatty acids for many functions, from muscle activity to cell growth.

Omega-3 fatty acids are derived from food. They can't be manufactured in the body. Fish oil contains two omega-3s called docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Dietary sources of DHA and EPA are fatty fish, such as salmon, mackerel and trout, and shellfish, such as mussels, oysters and crabs. Some nuts, seeds and vegetable oils contain another omega-3 called alpha-linolenic acid (ALA).

Fish oil supplements come in liquid, capsule and pill form.

People take fish oil for its anti-inflammatory effects.