The new study used data that had been gathered over decades for the Glostrup Population Studies, a series of studies done in Denmark that aimed to identify relationships between environmental factors and heart disease. All of the 3,277 participants were healthy adults upon entry. They answered diet, lifestyle, and health questionnaires, had a baseline health exam, and were followed for an average of 23 years.
Throughout the follow-up period, participants were monitored for ischemic heart disease, a condition in which blood flow to the heart muscle is compromised, usually due to coronary artery disease. When all of the data was analyzed, researchers observed:
Higher intakes of ALA and fish fats were each associated with reduced risk in men (those with the highest intakes of both ALA and fish fats had the lowest risk), but neither of these relationships reached statistical significance.
People who have factored flaxseed and ALA into their diets need not abandon their favorite products. Although they may not prevent ischemic heart disease, flaxseeds may have other benefits, such as diabetes prevention and alleviation of menopausal symptoms. But for wider protection, it makes sense for now to eat fish a few times per week or take a fish oil supplement.
The rest of your fat intake should supply a balance of fatty acids:
(Am J Clin Nutr 2011;doi: 10.3945/ajcn.111.018762)