by David Accomazzo

Add another notch to the ever-expanding evidence belt of omega-3 fatty acids' health benefits. A randomized, double-blind, placebo-controlled study published Monday showed that taking omega-3 fatty acids daily can help people with a history of heart failure stay out of the hospital and live longer.

Researchers in Italy gave almost 7,000 patients—78 percent males—with histories of heart failure either a placebo or 1 gram of omega-3 polyunsaturated fatty acids every day for almost four years, and the results, published in British medical journal The Lancet, showed what many have suspected for years: A daily supplement of omega-3 can help reduce the risk of heart failure.

The group receiving the supplements experienced a mortality rate 9 percent lower than those getting a placebo. Those receiving the supplement made 8 percent fewer hospital visits for heart-related reasons compared to those getting a placebo.

The study, which researchers say is the first to examine the effect of omega-3 fatty acids on heart failure, was an extension of a study by the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico, a group known for their studies of heart disease, said Annette Dickinson, a consultant the nonprofit Council for Responsible Nutrition, based in Washington, D.C.

"This is a study in people who already had heart failure to determine whether giving them omega-3 fatty acids would extend their lifespans," Dickinson said, adding that the results are "very consistent with previous studies in this area."

Omega-3 fatty acids affect the heart in 15 different ways, called "mechanisms of action," Dickinson said. Mainly, omega-3 fatty acids strengthen membranes in the heart and help prevent cardiac arrhythmias, a common cause of death in heart attacks.

The GISSI study did not examine the mechanisms of action, and additional research is needed to determine the most effective dose of omega-3 fatty acids, Dickinson said, noting that the 1 gram-a-day dose was slightly higher than the dosage used in most studies.