More than 50 percent fewer heart problems with omega-3s

Omega-3 fatty acids have protective effects on the heart and blood vessels, and reduce the likelihood of cardiovascular events significantly: high concentrations of EPA (eicosapentaenoic acid) and DHA (docoahexaenoic acid), in plasma, are associated with a reduction in cardiac risk of about 51 percent.

This was stated in a study published in the Journal of American Heart Association conducted by researchers from the Department of Epidemiology at the Harvard School of Public Health in Boston, USA.

PUFAs and cardiovascular risk

Current dietary guidelines recommend increasing the consumption of Omega-3 and Omega-6 and reducing that of saturated fats. These recommendations are based on the beneficial effects of long-chain polyunsaturated fatty acids (PUFAs) on cholesterol and blood pressure. Epidemiological and clinical studies also demonstrate the positive effects of PUFA consumption on the risk of cardiovascular events such as myocardial infarction, death from heart disease, and stroke. Despite this, some clinical research does not confirm additional benefits on the risk of cardiovascular mortality or morbidity due to Omega-3 consumption. 

These studies were mainly conducted in patients already at high cardiovascular risk who were taking statins, the drugs used for cholesterol reduction, or other therapies, making it difficult to demonstrate the benefits of small amounts of EPA and DHA. For these reasons, information obtained from large studies of heterogeneous populations about the relationship between PUFAs and cardiovascular risk is useful, especially when such studies examine concentrations of the fatty acids in the blood, rather than estimates of dietary intakes prone to measurement error.

A multi-ethnic study 

The research conducted by Boston University researchers involved 2,837 U.S. adults of different ethnic backgrounds (Caucasian, African American, Hispanic, and Chinese American) whose health status was monitored for 10 years. The study participants, whose average age was 62 years, had no cardiovascular disorders at the beginning of the research. The researchers analyzed the plasma concentration of fatty acids in each subject, and assessed the diet followed by means of a frequency questionnaire. The results showed that the test population exhibited low fish consumption, a major source of Omega-3, and that circulating levels of EPA and DHA were inversely related to the risk of cardiovascular disorders. Specifically, higher values of EPA and DHA were found to be associated with a risk reduction of more than 51 percent, while there was no relationship with alpha-linolenic acid or linoleic acid. The results also confirmed a weak relationship between alpha-linolenic acid and heart disease mortality but did not show risk reduction in association with linoleic acid. In addition, high plasma amounts of omega-3 were associated with a strong reduction in inflammatory mediators. Inflammation is widely recognized as an important factor in the 'origin of cardiovascular disease.

Circulating omega-3s reduce cardiovascular risk

According to the study authors, these results, in addition to suggesting increased consumption of EPA and DHA, extend observations on the protective effects of blood PUFAs against coronary heart disease and cardiovascular disease in different ethnic groups and those on diets low in Omega-3.

Source: de Oliveira Otto MC, Wu JH, Baylin A, Vaidya D, Rich SS, Tsai MY, Jacobs DR Jr, Mozaffarian D. Circulating and dietary omega-3 and omega-6 polyunsaturated fatty acids and incidence of CVD in the Multi-Ethnic Study of Atherosclerosis. J Am Heart Assoc 2013;2:e000606.