Omega-3 Fatty Acids May Not Prevent Heart Attacks

October 17th, 2012 - Posted in Nutriton - Tags: heart attacks, omega 3's

For more than 50 years, medical journals have published studies showing that omega-3 fatty acids in fish help prevent heart attacks. However, last year, three major studies showed that omega-3 fatty acids do not prevent fatal heart attacks, and a recent review of hundreds of studies on fish oils also shows that they may not prevent heart attacks (European Heart Journal, September, 2011).

REASONS FOR NEGATIVE STUDIES:
1) Fish oils may not prevent heart attacks. It is possible that fish prevent heart attacks because the fish oil acts in combination with other nutrients in fish, such as Vitamin D, iodine and selenium.
2) Drugs to treat high blood pressure, cholesterol and clotting may be so far more effective than omega-3s that the added benefit for omega-3s doesn’t show up in population studies in people taking medications.
3) People appear to receive maximum benefit from eating fish two times a week. More has not been shown to be better. People in Nordic countries eat large amounts of fish but the extra fish does not add further protection from heart attacks.

TYPES OF OMEGA-3S: Omega-3s occur as short chains in plants and long chains in fish. The long chain omega-3s appear to be far more effective in preventing heart attacks than the short chain ones in plants. Furthermore, the latest study shows that plant omega-3s may not prevent heart attacks (American Journal of Clinical Nutrition, published online September 2011).

DIFFERENT OMEGA 3S FROM PLANTS, FISH: Short chain omega-3 acids are found primarily in vegetable oils from canola and soybeans, flaxseed, and English walnuts. The human body cannot convert more than five percent of plant omega-3s to long chain fatty acids. This may explain why fish may prevent heart attacks and plant omega-3s do not or are far less likely to do so.

MERCURY: Nobody has shown, in controlled studies, that there is enough mercury in fish we eat to be harmful. Because of the potential of mercury to cause harm, the Food and Drug Administration recommends that women who are pregnant or nursing and young children eliminate the fish that contain the most mercury. They do not recommend that most people avoid fish because of mercury. Since mercury accumulates over many years, the largest and oldest fish have the most mercury: shark, swordfish, king mackerel, large tuna and tilefish.

WHICH FISH ARE BEST TO EAT?: Only deep water fish have been shown to help prevent heart attacks. Smaller salt-water fish such as salmon have a relatively short life span, so they have the least mercury and plenty of omega-3 fatty acids.

FISH OIL PILLS: Taking fish oil pills may not provide the benefits of eating fish. A recent report shows that fish oil pills lower triglycerides, which is good. High triglycerides increase risk for heart attacks and diabetes. However, fish oil supplements increase blood levels of the “bad” LDL cholesterol that causes heart attacks, and prevent blood from clotting to increase chances of bleeding (Nutrition, Metabolism & Cardiovascular Diseases, September 22, 2011). At this point, nobody has proven that fish oil pills prevent heart attacks.

GOOD DIET: Most experts recommend eating a healthful diet full of fruits, vegetables, whole grains, beans, seeds and nuts, and reducing your intake of sugared drinks and desserts, red meats, fried foods, and refined carbohydrates. You probably should also eat fish. Taking supplements or eating chemicals extracted from foods, such a fish oil pills, will not protect you from an unhealthy diet.

Drmirkin.com

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