By Kerry Grens
NEW YORK (Reuters Health) - Despite evidence suggesting omega-6 fatty acids might protect the cardiovascular system, a large new study of men finds the fats typically found in flax seeds and some vegetable oils do nothing to prevent heart failure.
"Although we know omega-6 fatty acids could influence blood pressure in a good way, we don't see that translate into a lower risk of heart failure," said Dr. Luc Djoussé, one of the authors of the study and a professor at Brigham and Women's Hospital in Boston.
Omega-6 fatty acids are relatively abundant in the Western diet, and are found in many cooking oils, such as sunflower and canola oils.
The effect of omega-6s on heart health has been controversial, however, according to William Harris, a professor at the University of South Dakota's Sanford School of Medicine and a senior scientist at Health Diagnostic Laboratory in Richmond, VA.
"Some people like me and others at the American Heart Association say higher intake of omega-6 is good for your heart from the heart attack point of view. Another group of people are saying high omega-6 is causing inflammation, so that's a bad thing," said Harris, who was not part of the current study.
One heart benefit linked by past research to omega-6 consumption is lower blood pressure.
Because high blood pressure is a risk factor for heart failure, Djoussé and his colleagues wanted to see if people who ate more omega-6s also had a lower risk of heart failure.
They used data from a long-term study of 22,000 male physicians in the U.S.
At the beginning of the study the men gave a blood sample, from which the researchers determined the level of omega-6 fatty acids in the men's bodies.
Over an average follow-up period of 17 years, 788 of the participants developed heart failure.
Djoussé's group compared these men to 788 others in the study, who were otherwise similar in age and other measures but had not experienced heart failure.
They found no differences between the two groups of men in the amount of omega-6 fats in their blood.
"There's no evidence of benefit. It's just one of those things where it doesn't appear to be playing a role in this particular disease," Harris told Reuters Health.
Djoussé said his findings suggest that researchers can shift their priorities away from looking to omega-6s as a possible way to reduce the risk of heart failure.
"If our focus is on heart failure, perhaps it's a good idea then to focus on other nutrients, other fatty acids," he told Reuters Health.
Another recent study by Djoussé and his colleagues found that getting a lot of omega-3 fatty acids in the diet by eating fish is tied to a lower risk of heart failure (see Reuters Health report of October 2, 2012).
SOURCE: http://bit.ly/SBfZ3z The American Journal of Clinical Nutrition, online November 28, 2012.