This is part of our ongoing The Best Kept Secrets to Healthy Aging spotlight. Each day, we will be posting some of the great information that’s packed into our book, The Best Kept Secrets to Healthy Aging.
What are Fish Oils?
The two most important fish oils are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These long names reflect their chemical structures; both EPA and DHA (most people use their nicknames) are very long-chain polyunsaturated fatty acids (PUFA) commonly found in most cold-water species of ocean fish, especially tuna, salmon and mackerel. The term “omega-3” recognizes the crucial difference in structure that distinguishes them from the “omega-6 PUFA” you are used to getting from vegetable oils.
This difference is so important that the human body cannot efficiently make EPA or DHA from the other fatty acids – the fish oils are dietary essentials that must be consumed from foods or dietary supplements in order for human life to thrive. (A very small amount of EPA may be made from plant-based omega-3 fatty acids, but this process is extremely inefficient, as extra steps are required by the body to perform this conversion.) Although a little EPA can be converted to DHA, obviously it would be much more efficient to consume both preformed EPA and DHA, which are already in forms that can be incorporated into cells. Almost all of the EPA and DHA that is consumed is absorbed and a study published in the journal Circulation found that the amounts of EPA and DHA circulating in the blood and being added into your cells and tissues are directly dependent upon how much of each of these fish oils is eaten.1 When EPA and DHA reach the body’s tissues and cells they are incorporated into the structural lipids that make up cell, nuclear and mitochondrial membranes. These membranes absolutely require EPA and DHA in order to function properly – they aid in cell-to-cell communication and facilitate the flow of nutrients into cells as well as the removal of toxins from cells. Improperly incorporated fatty acids (not the preferential ones like EPA and DHA) can hinder these important cellular functions and impair cellular metabolism, leading to unhealthy cells and therefore unhealthy organs. EPA and DHA are thus essential components of every cell in the body.
Tomorrow’s topic: Fish Oils and a Healthy Heart
1. Harris WS, Sands SA, Windsor SL, Ali HA, Stevens TL, Mgalski A, Porter CB, Borkon AM. Omega-3 fatty acids in cardiac biopsies from heart transplantation patients. Correlation with erythrocytes and response to supplementation. Circulation 2004;110:1645-1649.