IMAGE: This is a table that evaluates the results of the meta-analysis. view More
Photo credit: Maki et al
Findings from a new study published in the Journal of Clinical Lipidology showed that in 14 randomized controlled trials (RCTs) of 71,899 people, EPA and DHA omega-3 consumption increased the risk of cardiac death by a statistically significant Average of 8 percent decreased. Cardiac death accounts for about two-thirds (about 405,000) of all cardiovascular disease deaths in the United States, and 42 percent (7.4 million) worldwide each year (1.2). This is the first published meta-analysis that included cardiac death (also known as “coronary mortality”) as the primary endpoint and the most comprehensive review of the evidence to date.
The meta-analysis showed an even greater risk reduction of 17 percent in groups with elevated triglycerides or LDL cholesterol. These results are consistent with the hypothesis that EPA and DHA omega-3 fatty acids are most useful in reducing cardiac death in those at higher risk (see table). This is important because the National Center for Health Statistics estimates that 25 percent of adults living in the United States have triglyceride levels ≥ 150 mg / dL (3) and 27 percent have LDL cholesterol levels ≥ 130 mg / dL (4). The greatest reduction in cardiac death rates – a risk reduction of nearly 30% – was seen in studies using dosages greater than 1 gram of EPA and DHA per day.
The RCTs reviewed were longer than six months and examined cardiac death as the primary outcome, comparing the frequency of cardiac death events between the omega-3 group and the control group. The researchers reviewed the studies published through December 2016, which included both dietary supplements and pharmaceutical omega-3 interventions. In the omega-3 groups, 1,613 cardiac deaths were registered (4.48 percent of the subjects), compared with 1,746 cardiac deaths in the control groups (4.87 percent of the subjects). In this study, the effects of EPA and DHA consumption by fish on the risk of cardiac death were not investigated because no randomized, controlled studies exist. However, observational studies of EPA and DHA from fish also show an advantage in reducing risk (5).
“It is important to note that these results are consistent with the conclusions of the American Heart Association’s recent Science Advisory that EPA and DHA omega-3 treatment are ‘appropriate’ for secondary prevention of coronary heart disease and sudden death.” said Dr. Kevin Maki, lead study author and chief scientist, Center for Metabolic and Cardiovascular Health of Biomedical Research in the Midwest. “A notable feature of omega-3 supplementation with EPA and DHA is the low risk associated with their use. Because of the low risk of side effects, even a modest benefit is clinically significant.”
“This study is important because it examines the effects of omega-3 fatty acids on a specific outcome in coronary artery disease,” said Dr. Harry B. Rice, Vice President of Regulatory and Scientific Affairs at GOED, who funded the study. “A number of studies in recent years have questioned the benefits of omega-3s in cardiovascular disease. However, to understand the role of omega-3s in the cardiovascular system, research must focus on focus on a specific disease rather than all cardiovascular outcomes combined. This is an important nuance that this meta-analysis helps clarify. “
Consuming adequate amounts of EPA and DHA is part of a balanced diet and healthy lifestyle. The Dietary Guidelines for Americans and the American Heart Association recommend weekly seafood / fatty fish consumption (6.7). Two servings a week provide 250-500 mg of EPA and DHA per day. Additionally, the AHA recommends 1 gram of EPA and DHA per day for people diagnosed with heart disease. Increasing your omega-3 intake is easy and inexpensive. The cost of omega-3 supplements ranges from $ 10 to $ 60 per month, depending on the type of fish, and from $ 10 to $ 25 per month for oily fish. Omega-3 is also generally considered safe; The US FDA allows up to 3 grams per day and the EFSA, the European Food Safety Authority, does not report safety problems with up to 5 grams per day. If consumers are allergic to fish or want to take higher doses, they should consult their doctor.
One limitation of the results of the present meta-analysis is that some of the included studies were small or had suboptimal study designs. For example, two of the largest studies, GISSI-Prevenzione and JELIS, were controlled but did not use placebos. While this increases the possibility of bias / mix-up, it is less likely to lead to a fatal result, and removing individual studies from analysis did not change the results. In addition, in most studies, baseline omega-3 levels were not available at baseline and post-intervention, making it difficult to determine how much blood levels actually increased from supplementation.
The meta-analysis was funded by the Global Organization for EPA and DHA Omega-3 Fatty Acids (GOED), but GOED was not involved in the design or interpretation of the results.
About EPA and DHA Omega-3
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are omega-3 fatty acids with which the body supports the cells in their optimal function. They are typically found in oily fish such as salmon, tuna, or mackerel, but are also easily available in omega-3 supplements made from fish oil, krill oil, or algae, or in fortified foods. The two nutrients play key roles in heart health, brain health, and eye health throughout life. The FDA has approved a qualified health claim in the US that states, “Supportive but inconclusive research shows that consumption of EPA and DHA omega-3 fatty acids can reduce the risk of coronary artery disease.” Many governments and scientific organizations recommend consuming 250-500 mg of EPA and DHA per day (8).
The Global Organization for EPA and DHA Omega-3 Fatty Acids (GOED) is a trade association that represents around 200 companies worldwide that are active in the EPA and DHA omega-3 industry. GOED’s membership spans every segment of the omega-3 supply chain, from fishing and seafood companies to refineries, nutritional supplement manufacturers to food and beverage retailers and pharmaceutical companies. The members of GOED agree to adhere to product quality and ethical standards that are as strict or more stringent than any regulations in the world. GOED is specifically focused on addressing the under-consumption of EPA and DHA in human nutrition by promoting the global consumption of EPA and DHA and protecting consumers by ensuring that members produce quality products.
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