Numerous medical studies have linked diets including fish to a lower risk of heart disease. The findings have driven a billion-dollar market in fish oil supplements marketed as omega-3 fatty acids. Eating fish has been recognized as good preventive medicine for a healthy diet. But for those who already have developed heart disease, a new report suggests that fish oil supplements are probably a waste of money.
Omega-3 and Eskimos
Scientists got the idea that eating fish oil could prevent heart disease back in the 1970s by observing low rates of heart disease in Greenland Eskimos who ate a diet heavy on the fish. Other studies since then have suggested that the omega-3 fatty acids DHA and EPA reduce inflammation and arterial plaque.
The heart healthy benefits of omega-3s in fish have been convincing enough that the latest release of Dietary Guidelines for Americans recommends up to three servings of fish a week. Doctors also recommend taking omega-3s in the form of fish oil supplements to protect the heart. But a new analysis of studies on the effect of fish oil on cardiovascular disease risk casts doubt on the value of fish oil supplements for heart patients.
Analyzing fish oil data
Clinical trials of the benefits of fish oil on heart health have produced mixed results. To find a definitive answer, scientists in South Korea sifted through more than 1,000 fish oil research reports and selected the most well-designed studies. They analyzed data from 14 randomized, placebo-controlled studies involving more than 20,000 patients with a history of heart disease.
Participants the trials were treated with DHA or EPA in the form of purified fish oil supplements. They were tracked for at least a year to determine whether omega-3 fatty acids had an effect on their risk of heart attacks, strokes, angina and heart failure. The analysis, published in “Archives of Internal Medicine,” found “insufficient evidence” that fish oil supplements prevented future cardiovascular events.
Benefit for healthy people?
The authors noted that taking fish oil may still have a preventive benefit for people who haven’t already developed major cardiovascular problems. Other current studies not included in the South Korean report are following thousands of healthy adults to determine whether fish oil supplements can prevent heart attacks and strokes in people with no history of heart disease.
Eat real fish, not supplements
Of course, eating fish has no downside. The authors note that natural sources of omega-3 fatty acids may be more potent than pills. They suggest you spend your money on real fish instead of fish oil supplements whether you have a history of cardiovascular disease or not. You’ll be getting a more reliable source of omega-3 and you’ll be displacing other unhealthy sources of protein, such as processed food and red meat.