Omega-3 fatty acids - those "healthy" fats found primarily in fish - have been in the news a lot lately, thanks to research showing their potential to possibly lower risk of heart disease. Finnish researchers have studied not only how much omega-3s people ate, but how much their blood contained, to see if there was an association between blood levels of omega-3s and the risk for cardiovascular-related death. Their results are published in the American Journal of Clinical Nutrition.

Studying patients with coronary artery disease

Investigators in Finland studied 285 men and 130 women (average age 61) with coronary artery disease. They analyzed the participants' food records to determine the amount of omega-3s they ate and they also measured the amount of omega-3s contained in blood samples collected after a 12-hour fast.

The researchers followed the participants for 5 years and documented the number of deaths from cardiovascular causes, as well as the number of nonfatal cardiovascular events, such as heart attacks and strokes. Using statistical analyses, they calculated the link between blood levels of omega-3s and risk of death.

High omega-3 levels associated with lower risk for death

During the study, 36 study participants died, 21 had heart attacks, and 12 had strokes. Among all study participants, those who had the highest concentrations of the omega-3 fatty acid docosahexanoic acid (found in fish) had a 69% lower risk of death compared with those with the lowest concentrations. Similar results were found for two other omega-3 fatty acids (eicosapentanoic acid and alpha-linolenic acid), although those results were not what scientists deem "statistically significant."

How omega-3s may influence cardiovascular risk

Research is ongoing to determine the exact mechanism by which omega-3s positively influence cardiovascular health. It may have to do with their effects on lowering triglycerides (blood lipids) or by making blood platelets less "sticky" and thereby less likely to cause blood clots. They may also affect the heart's rhythm. All of these theories, however, require more study.

Increasing your intake of omega-3s

In the meantime, many health experts have recommended that consumers replace less healthful fats in their diets, such as saturated and trans fats, with more healthful fats, including omega-3s. Good sources of omega-3s include fatty fish, ground flaxseed and flaxseed oil, canola oil, and soybean oil. Just remember that all fats have roughly the same number of calories, so it's very important to substitute healthful fats for less healthful ones - not just add healthful fats to your existing diet.