Cardiovascular Disease and the Omega-3
For several decades, it has been known that Greenland Eskimos experience lower rates of heart disease than populations lacking in fish consumption. Their diet, comprised of cold-water fish, seal, and whale, is high in Omega-3 content. Since the observation that populations high in fish consumption have lower rates of heart disease and other health problems, compelling scientific evidence has amassed showing that the Omega-3 essential fatty acids EPA and DHA help protect a healthy heart and also reduce the risks of cardiovascular disease. The American Heart Association (AHA) now recommends the dietary intake of Omega-3s for both individuals with, and without, heart disease, and the US Food and Drug Administration has even issued a qualified health claim for the role of Omega-3s in helping to reduce coronary heart disease.
A multitude of clinical trials have shown that Omega-3 fatty acid supplements can reduce the risk of a number of different cardiovascular events, including sudden death, arrhythmias, heart attacks, and strokes. Studies of individuals who have survived a heart attack show that Omega-3s may decrease the risk of a second heart attack by nearly 30%, while individuals consuming even a moderate amount of Omega-3s may reduce their risk of a stroke by 50%. While it is not precisely known why Omega-3s confer such cardiovascular protective effects, it is likely that they work through several different mechanisms of action.
The Omega-3s EPA and DHA help reduce platelet aggregation, which inhibits the build-up of plaque and blood clots in arteries supplying the heart and the brain. In addition to their effect on platelets, Omega-3s have potent anti-inflammatory effects, and act to decrease harmful inflammatory mediators such as prostaglandins, leukotrienes, and interleukins, all of which may contribute to vascular damage. Numerous studies also confirm the important role that Omega-3s play in decreasing high triglycerides, a type of fat that can lead to arterial damage and now recognized as an independent risk factor for heart disease. The AHA recommends that patients who need to lower their triglycerides should take 2-4 grams of EPA + DHA per day.
Other potential cardiovascular benefits of Omega-3s include lowering blood pressure and improving vascular tone. Demographic studies of certain populations that consume more fish in their diets suggest that Omega-3s may also improve HDL, the body’s “good cholesterol.” Some clinical trials suggest that Omega-3s may also improve the body’s balance of HDL and LDL cholesterol, though further studies will help clarify just how Omega-3s influence this cholesterol profile.
The American Heart Association now recommends the consumption of Omega-3 essential fatty acids for overall heart health, adding further that individuals with documented heart disease consume about 1 gram per day of EPA + DHA. Individuals with high triglycerides may benefit from higher doses of EPA and DHA but treatment should be carried out under a physician’s care. Supplementing one’s diet with an adequate amount of Omega-3s to promote cardiac health can be safely done with high-purity supplements free of environmental contaminants.
References for Cardiovascular Disease and the Omega-3
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