Omega-3 fatty are a class of healthy fats essential for human nutrition. Omega-3 must be obtained through diet so it is not produced by the body on its own. These fatty acids are essential for normal cellular function, and also help to protect the body from the development of several life-threatening conditions
There are three types of omega-3s. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are long-chain fatty acids found in fatty fish such as salmon, herring and mackerel. These are the types of body uses most efficiently. A third type is alpha-linolenic acid (ALA), a short-chain fatty acid found in plants. The body must convert ALA to the long chain forms before it can be utilized.
A meta-analysis published in the October 18, 2006, Journal of the American Medical Association shows that omega-3 from fish reduced the risk of dying from heart disease by 36 percent. Benefits were found in only one to two servings of fish per week, compared with an average daily intake of 250 milligrams of combined EPA and DHA. Omega-3 has been shown to reduce the risk of heart attack, stroke and heart rhythm abnormalities in people with and without known heart disease.
Omega-3 fatty acids appear beneficial in preventing or slowing the progression of neurodegenerative diseases. According to a study published in the April 18, 2007, Journal of Neuroscience, brakes dietary consumption of DHA development of beta-amyloid and tau protein, two proteins that are responsible for the development of Alzheimer’s disease. Some researchers believe that omega-3 may protect against Parkinson’s disease in the same way -. By slowing the accumulation of protein in brain tissue
Omega-3 deficiency is one of the most common nutritional deficiencies in the United States. While the ideal dietary ratio of omega-6 to omega-3 is believed to be around one to one, the ratio of the average Western diet about fifteen to one. A 2009 study conducted at the Harvard School of Public Health estimates that low dietary omega-3 is the sixth deadliest preventable risk factor in the United States, with approximately 84,000 annual deaths attributed to this factor. Signs of omega-3 deficiency include fatigue, depression, difficulty concentrating, dry skin and brittle nails and hair.
Oily fish is considered the best food source of omega-3 fatty acids due to the presence of both EPA and DHA. Salmon, mackerel, bluefish, swordfish and sardines are high in these fatty acids, with about 2 grams of omega-3 per 4-ounce serving. Tuna, cod, scallops and crabs also contains omega-3 in minor amounts. Vegetarian sources of omega-3, in the form of ALA are walnuts, flaxseed, soybeans and canola oil.