The Benefits of Fish Oils

Appears in
On Food and Cooking

By Harold McGee

Published 2004

  • About

As we’ll, life in cold water has endowed sea creatures with fats rich in unusual, highly unsaturated omega-3 fatty acids. (The name means that the first kink in the long chain of carbon atoms is at the third link from the end.) The human body can’t make these fatty acids very efficiently from other fatty acids, so our diet supplies most of them. A growing body of evidence indicates that they happen to have a number of beneficial influences on our metabolism.

One benefit is quite direct, the others indirect. Omega-3 fatty acids are essential to the development and function of the brain and the retina, and it appears that an abundance in our diet helps ensure the health of the central nervous system in infancy and throughout life. But the body also transforms omega-3 fatty acids into a special set of calming immune-system signals (eicosanoids). The immune system responds to various kinds of injuries by generating an inflammation, which kills cells in the vicinity of the injury in preparation for repairing it. But some inflammations can become self-perpetuating, and do more harm than good: most importantly, they can damage arteries and contribute to heart disease, and they can contribute to the development of some cancers. A diet rich in omega-3 fatty acids helps limit the inflammatory response, and thus lowers the incidence of heart disease and cancer. By reducing the body’s readiness to form blood clots, it also lowers the incidence of stroke. And it lowers the artery-damaging form of blood cholesterol.