MORE IN OMEGA-3s
Omega-3s are essential fatty acids. This means they are essential to health, but because they cannot be generated by the body, they must be obtained from food. One of the richest sources for Omega-3s is fish (particularly fatty fish like mackerel, albacore tuna, lake trout, and salmon), but other sources are tofu and other soy products, as well as canola, walnuts, flaxseed, and the oils derived from these foods. Free-range chicken eggs, milk and cheese from grass-fed cows, and grass-fed meat are also sources of Omega-3s.
There are three types of Omega-3 fatty acids. Eicosapentaenoic acid and docosahexaenoic acid, both of which are found in fish oil, are the most valuable since they’re the forms that the body requires. The third variety, alpha-linolenic acid is the version that is found in soy products, canola, nuts and flaxseed. The body can synthesize EPA and DHA from ALA, but scientists say it is best to consume EPA and DHA themselves.
Scientists are still studying the benefits and effects of Omega-3s. The most apparent benefit to an Omega-3-rich diet is heart health; the American Heart Association has discovered that Omega-3s help reduce blood clots, arrhythmias, triglyceride levels and inflammation, and also can slightly reduce blood pressure.
But Omega-3s have other bodily benefits. Because of the way they can reduce plaque buildup and blood clots in the arteries, they can help protect against stroke. Omega-3s can also help people with diabetes, by lowering their triglyceride levels and raising their HDL (“good” cholesterol) levels. And arthritics can benefit from consuming Omega-3 fatty acids to reduce joint tenderness and stiffness.
Some Omega-3 fatty acids (particularly EPA) can help increase levels of calcium in the body and improve bone strength, meaning that women with osteoporosis can help decrease bone loss and density.
Because Omega-3s can also affect brain function, some studies have shown that people who do not get enough Omega-3 fatty acids may be at an increased risk for depression.
Omega-3 fatty acids need to work in concert with Omega-6 fatty acids (Linoleic Acid), but most of us get plenty of Omega-6s in our diet; in fact, many Americans’ diets have too much Omega-6, in relation to Omega-3 fatty acids. The recommended balance is up to four times more Omega-6 fatty acids than Omega-3s, but most diets have more than 11 times more Omega-6. Omega-6 fatty acids can be found in cooking oils, such as soybean oil, sunflower oil, and vegetable oil.
How much Omega-3 should be in your diet to reap these benefits? Studies show that between .5 and 1.8 grams of EPAs and DHAs can significantly reduce heart disease death, as can 1.5 to 3 grams a day of ALAs. According to the 2000 American Heart Association dietary guidelines, at least two fish servings a week is a good guideline.
History
Scientists first distinguished Omega-3 and Omega-6 fatty acids in 1930, seven years after they discovered that there were some fatty acids vital for bodily function that the body could not manufacture itself.
In the 1980s, Danish scientists discovered that Greenland Eskimos, whose diet is high in fish, seal and whale blubber, have no instances of heart attacks, while Eskimos who move to Copenhagen have the same heart problems as the Danes.
Other findings showed that those living in Crete and in Japan both have long life expectancies, due to their diets that are high in sources of Omega-3.
Americans became more aware of the importance of Omega 3s in the diet in 1996, when the American Heart Association released a Science Advisory titled “Fish Consumption, Fish Oil, Lipids and Coronary Heart Disease,” which correlated the consumption of the fatty acids to a reduction of heart problems. The study spurred additional research and findings about the benefits of Omega 3s on cardiovascular disease, and the AHA has since updated its finding in the 2002 Scientific Statement, “Fish Consumption, Fish Oil, Omega-3 Fatty Acids and Cardiovascular Disease.”
Context
As with many nutrients, it is possible to have too much of a good thing. The AHA cautions that a high intake of Omega-3s could cause excess bleeding, and recommends that anyone taking more than 3 grams of Omega-3s from supplements should only do so if they have been advised such a dosage by a physician. In fact, people who eat more than three grams of Omega-3 fatty acids daily could be at an increased risk for hemorrhagic stroke.
What’s more, eating large quantities of fish also puts you at risk for poisoning from mercury and other contaminants. Older, larger, predatory fish have the highest concentration of mercury, PCBs, dioxins and other substances. The fish that have the highest levels of mercury include shark, swordfish, tilefish and king mackerel. Women who are pregnant or nursing, as well as young children, should get their Omega-3s from smaller, younger fish, but the AHA says it’s safe for others to eat up to 7 ounces of high-mercury fish per week.
External Links:
Wikipedia - Omega-3 Fatty Acids [1]
American Heart Association [2]
Best Foods and Fish for Omega-3 [3]
University of Maryland Medical Center [4]
Omega-3 Information Service [5]
Linus Pauling Institute at Oregon State University, Micronutrient Information Center [6]
Further Reading:
The Omega-3 Connection: The Groundbreaking Antidepression Diet and Brain Program [7] by Andrew Stoll
Omega 3 Oils: A Practical Guide [8] by Donald Rudin and Clara Felix
The OMEGA-3 Miracle: The Icelandic Longevity Secret that Offers Super Protection Against Heart Disease, Cancer, Diabetes. Arthritis, Premature Aging, and Deadly Inflammati [9] by Garry Gordon, M.D.