Omega-6 fatty acids found in vegetable oils, nuts and seeds are good for your heart, says a new study.
The research has been published in Circulation: Journal of the American Heart Association.
The association has recommended that people aim for at least 5 percent to 10 percent of calories from omega-6 fatty acids.
Recommended daily servings of omega-6 depend on physical activity level, age and gender, but range from 12 to 22 grams per day.
Omega-6, and the similarly-named omega-3 fatty acids (found in fattier fish such as tuna, mackerel and salmon), are called polyunsaturated fatty acids (PUFA), and can have health benefits when consumed in the recommended amounts, especially when used to replace saturated fats or trans fats in the diet. Omega-6 and omega-3 PUFA play a crucial role in heart and brain function and in normal growth and development.
PUFA are "essential" fats that your body needs but can't produce, so you must get them from food.
"Of course, as with any news about a single nutrient, it's important to remember to focus on an overall healthy dietary pattern - one nutrient or one type of food isn't a cure-all," said William Harris, Ph.D., lead author of the advisory.
To reach the conclusion, the advisory reviewed a meta-analysis of randomized, controlled trials, and more than two dozen observational, cohort, case/control and ecological reports.
Observational studies showed that people who ate the most omega-6 fatty acids usually had the least heart disease. Other studies examined blood levels of omega-6 in heart patients compared with healthy people and found that patients with heart disease had lower levels of omega-6 in their blood.
In controlled trials in which researchers randomly assigned people to consume diets containing high versus low levels of omega-6 and then recorded the number of heart attacks over several years, those assigned to the higher omega-6 diets had less heart disease.
A meta-analysis of several trials indicated that replacing saturated fats with PUFA lowered risk for heart disease events by 24 percent.
"When saturated fat in the diet is replaced by omega-6 PUFA, the blood cholesterol levels go down. This may be part of the reason why higher omega-6 diets are heart-healthy," Harris said.