Researchers from the Harvard School of Public Health studying the role of fish consumption and risk of stroke among men, have found that men who eat fish as little as twice per month significantly reduce their risk for ischemic stroke compared to men who eat fish less often or not at all. The findings are in the December 25, 2002 issue of the Journal of the American Medical Association.
Selecting qualified participants from the Health Professionals Follow-up Study, the researchers tracked the diet and health outcomes of more than 43,000 male participants for 12 years. Using detailed food frequency questionnaires, participants were asked how often they ate fish, ranging from never or less than once per month to six or more times per week. The men in the study were also asked about four different fish items: canned tuna fish, dark meat fish such as mackerel, salmon sardines, bluefish and swordfish; other fish and shrimp, lobster, or scallops served as a main dish.
The researchers assessed the effect of long-chain omega-3 polyunsaturated fatty acid, a constituent of fish believed to have healthful effects, on the risk of ischemic stroke (blood flow to a certain area of the brain is interrupted). They found that men who ate even a small amount of fish, one to three times per month from any of the fish categories, reduced their risk of ischemic stroke by 40 percent compared to the men in the study who ate fish less often or not at all. There was no evidence of further risk reduction of stroke by consuming fish more often. Men who ate fish five times per week received the same benefits as those in the study who ate fish two or three times per month.
Ka He, co-author of the study and a researcher in the Departments of Nutrition and Epidemiology at the Harvard School of Public Health said, “We weren’t surprised to find that adding fish to one’s diet would prove beneficial, but we were surprised to see how small amounts of fish and omega-3 fatty acids, eaten regularly, can significantly reduce the risk of ischemic stroke for men. The message is clear for men, incorporate fish, whether it’s lobster, canned tuna or salmon, into your diet and reduce the risk for stroke.”
The study was supported by a grant from the National Institutes for Health.