HHS: Fish Oil Beneficial to Heart Health

WASHINGTON--Fish oil can help reduce deaths from heart disease, according to new evidence reports released by the Agency for Healthcare Research and Quality (AHRQ), an arm of the Department of Health and Human Services (HHS). AHRQ released three reports on omega-3 essential fatty acids (EFAs) and cardiovascular function; the reports were prepared by the Tufts-New England Medical Center in Boston. The reviewers concluded long chain polyunsaturated fatty acids (LC-PUFAs) reduce heart attack, reduce triglyceride levels, slightly lower high blood pressure, reduce arrthymia and reduce risk of coronary artery re-blockage after angioplasty.

"These findings will help health care professionals and the public understand which benefits of omega-3 fatty acids have been scientifically proven and pinpoint areas where additional evidence is needed," said Carolyn M. Clancy, M.D., director of AHRQ. "Translating scientific evidence into information that can be used to improve health and health care is key to AHRQ's mission."

For the review on omega-3 supplementation and cardiovascular disease (CVD) outcomes, the Tufts researchers reviewed 39 studies assessing CVD clinical outcomes, as well as 12 secondary prevention studies. They found strong evidence supporting the hypothesis that fish or fish oil reduces all-cause mortality and various CVD outcomes; evidence on alpha-linoleic acid (ALA, a precursor to longer-chain omega-3s) independent of fish oil was inadequate to draw a conclusion. The complementary reviews examining fish oil's effects on CVD risk factors and arrhythmia found protective effects including lowering triglyceride levels (in a dose dependent manner) and preventing ischemia-induced arrhythmia.

AHRQ also released a report about omega-3s and asthma (conducted at the University of Ottawa, Ontario), and one about EFAs and conditions including inflammatory bowel disease and rheumatoid arthritis (conducted at Southern California-RAND EPC, Santa Monica). Researchers used 31 reports for the asthma review, but found there was a lack of consistent evidence and a lack of well-conducted studies; therefore, they did not draw a conclusion on omega-3s influence on mediators of inflammation in asthma. Similarly, the California researchers found mixed effects from studies on omega-3s in treating inflammatory bowel disease, kidney disease and osteoporosis, and no discernible effect on rheumatoid arthritis.

"The reports describe some positive findings as well as a number of areas where data are insufficient to draw conclusions about the efficacy and safety of omega-3 fatty acids," said Paul M. Coates, Ph.D., director of the Office of Dietary Supplements at the National Institutes of Health (NIH). "[We] will use these reports to develop appropriate research agendas for omega-3 fatty acids that will fill these gaps in knowledge."

Summaries of the evidence reviews are available online (www.ahrq.gov/clinic/epcindex.htm) or by contacting AHRQ at (800) 358-9295.