Fish May
Lower Stroke Risk in Men: Study
Tuesday, December 24, 2002
Men who eat just one serving of fish a month may
have a lower risk of the most common type of stroke, which occurs when blood
flow to the brain becomes blocked, new study findings indicate. However, eating
more fish may not add much benefit when it comes to lowering the risk of
hemorrhagic stroke, which is caused by bleeding in the brain.
In the study of more than 43,000 men aged 40 to 75
years, eating fish one to three times a month was associated with a 43% lower
risk of ischemic stroke. But men who reported eating fish at least five times a
week were only slightly more protected, with a 46% lower risk. Exactly how such
a small amount of fish, which is rich in omega-3 fatty acids, may lower stroke
risk is not clear. However, omega-3 fatty acids may have several different
effects on the body, including a reduction in the "stickiness" of
platelets, which help form blood clots. Because clots are the cause of 80% of
strokes, preventing them from forming may ward off strokes.
The study adds to a growing body of research into
the effect of fish on stroke risk. One recent report found that women who ate
at least five servings of fish a week had a 62% lower risk of stroke, compared
with those who ate fish less than once a month.
"Our findings suggest that eating fish once
per month or more can reduce the risk of ischemic stroke in men," Dr. Ka
He from the Harvard School of Public Health in Boston, Massachusetts and
colleagues conclude. Their findings are published in the December 25th issue of
the Journal of the American Medical Association.
The researchers followed men taking part in the
Health Professional Follow-up Study, a large national trial. The men in the
study, who did not have heart disease or diabetes at the outset, filled out
detailed questionnaires about their usual diets. Over the next 12 years, the
researchers documented 608 strokes, including 377 ischemic strokes and 106
hemorrhagic strokes (they found no association between omega-3 and this rare
type of stroke).
Reference:
Journal of the American Medical Association 2002;288:3130-3136.