Omega-3 fatty acids: Good for Your Heart

Narinder Duggal, MD, FRCPC

“Fats are good for your heart.” Doesn’t that sound amazing? Yes, fats are good for your heart, if they are omega-3 fatty acids. Omega-3 fatty acids are polyunsaturated fatty acids and are classified as essential because they cannot be synthesized in the body; they must be obtained from food. There is mounting evidence suggesting that adequate intakes of omega-3 fatty acids assist in the protection against cardiovascular diseases.

Cardiovascular diseases (CVD) are a group of disorders of the heart and blood vessels that increase the risk of heart attack, heart failure, sudden death, stroke and cardiac rhythm problems. CVD claims more than 17 million deaths a year and by 2030, almost 23.6 million people will die from CVD’s mainly heart disease and stroke.^1,2 CVD is primarily a lifestyle disease and in addition to adopting a healthy lifestyle and diet, an increase in the consumption of omega-3 fatty acids can help prevent the development or aggravation of this disease.

There are many preventable risk factors associated with CVD. The major risk factors include tobacco use, alcohol use, high blood pressure (hypertension), high cholesterol, obesity, lack of physical activity and unhealthy diets.³ Scientists have recently added one more factor to this list and that is omega-3 index, the measurement of the proportion of omega-3 fatty acids as a percentage of total fatty acids in red blood cells.^4-6 An omega-3 index greater than 8% is associated with 90% less risk for sudden cardiac death, as compared to an omega-3 index of less than 4%.⁷ Some researchers have assessed omega-3 index risk zones, especially for sudden cardiac death as high risk is less than 4%; intermediate risk, 4-8%; and low risk more than 8%.⁵

Omega-3 fatty acids confer a number of beneficial effects on our cardiovascular system. Epidemiological studies have shown an ability to reduce triglyceride levels, blood pressure, platelet aggregation, arrhythmia, and atherogenesis.⁸ Clinical studies suggest that high dietary intake of the omega-3 fatty acids may lower the incidence of heart failure, and that omega-3 fatty acid supplementation prolongs event-free survival in patients with established heart failure.⁹ Three large controlled trials with 32,000 subjects concluded that omega-3 fatty acids supplementation showed reductions in cardiovascular events by 19% to 45%.¹⁰Supplementation of omega-3 PUFA (Poly-unsaturated fatty acids) is also indicated as monotherapy in the treatment of hypertriglyceridemia.¹¹

The GISSI-Prevention trial randomly assigned more than 11,000 patients with recent heart attacks to four treatment groups; omega-3 fatty acids (850 mg capsule daily), vitamin E, both, or neither (control). The study subjects in all four groups were followed for 3.5 years.¹² Subjects given omega-3 fatty acids had a 20% lower death rate from coronary heart disease than subjects in the vitamin E and control groups. Omega-3 fatty acids were particularly effective in preventing sudden cardiac death (45% reduction in sudden cardiac death).

Increasing in-vitro and in-vivo evidence has demonstrated that omega-3 fatty acids can prevent fatal cardiac arrhythmias.¹³ It is believed that omega-3 fatty acids are able to modulate the autonomic control of the heart by affecting the cardiac ion channels, especially sodium and calcium channels. The autonomic nervous system is involved in the pathogenesis of sudden cardiac death (SCD). Heart rate variability (HRV) is a non-invasive marker of cardiac autonomic function and an attenuated HRV is a predictor for the risk of SCD and arrhythmic events. Many studies have demonstrated a positive association between cellular content of omega-3 fatty acids and HRV. Supplementation with omega-3 fatty acids seems to increase HRV and thereby decrease the risk of arrhythmic events and SCD.^14-17 Omega-3 fatty acids administration has also been associated with a lower incidence of atrial fibrillation in patients who underwent cardiac surgery.¹⁸ Another study found that when post-MI patients were given 5.2 g of omega-3 fatty acids daily for 12 weeks their HRV significantly increased.¹⁹

Cardiac societies recommend the intake of 1 g/day of the omega-3 fatty acids for cardiovascular disease prevention, treatment after a myocardial infarction, prevention of sudden death, and secondary prevention of cardiovascular disease.7 Some experts have recommended a dose of 1g/day for individuals with known coronary heart disease and a dose of 250-500 mg daily for individuals without disease.²⁰

Omega-3 fatty acid therapy continues to show great promise in primary and, particularly in secondary prevention of cardiovascular diseases. Several observational and experimental studies show the beneficial effects of omega-3 fatty acids in cardiovascular disease. The results from such studies justify supplementation of omega-3 fatty acids. Because of the remarkable cardioprotective effects, omega-3 fatty acids should be increased in the diet to promote cardiovascular health. Synergy Therapeutics offers one of the most pure and potent omega-3 fatty acids, EPACOR. EPACOR contains 1,000 milligrams of the omega-3 fatty acids per serving (EPA and DHA). Visit our product page to learn more.

References:

1.    http://www.who.int/cardiovascular_diseases/en/. (Open Link)
2.    http://www.who.int/mediacentre/factsheets/fs317/en/index.html. (Open Link)
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