DHA and cardiovascular health

During the last 30 years many studies have been conducted on the benefits of omega-3 in the cardiovascular system. In 1944, Sinclair described how odd it was the occurrence of cardiovascular diseases among Greenland Eskimos, whose diet was rich in seals, whales and fish. Furthermore, over 30 years ago, Bang and Dyberg noted that despite taking a diet low in fruits, vegetables and complex carbohydrates and high in saturated fat and cholesterol, the levels of cholesterol and triglycerides in the blood of Eskimos were lower than similarly aged adults in the neighboring Denmark, where the risk of myocardial infarction was also higher. These observations led to speculations about the protective role of omega-3 in what became known as the Eskimo Factor.

Since then, numerous studies have been conducted that highlight the importance of omega-3 to support cardiovascular health (ie. DART studies, GISSI, JELIS,…). Both EPA and DHA promote cardiovascular health, although each fatty acid works through different mechanisms of action. The American Heart Association or AHA (American Heart Association) recommends taking 1,000 mg omega-3 / day.

DHA, like EPA, helps reduce blood triglycerides, a type of fat which in excess can become a threat to the cardiovascular health. Furthermore, studies have shown that DHA has a moderately hypotensive and antiarrhythmic effect.

There is a widespread belief that omega-3 lower cholesterol levels. However, according to the scientific literature, this is not exactly true. The total cholesterol-lowering effect of omega-3 fatty acids is in all cases rather moderate and not significant.

DHA is very good at increasing ‘good cholesterol’, also known as HDL. Furthermore, DHA causes ‘bad cholesterol’ molecules (known as LDL) to increase in size, making them less atherogenic, ie. do not stick to the walls of the blood vessels as easily (and thus prevents from ‘blocking ‘ them). Therefore, this second feature, is also interesting for the cardiovascular health.

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