A Study Shows That Some Fish is Better Than None

Source: Tufts University
February 14, 2003

You don't have to be a huge fan of fish to garner some of the health benefits of this 'heart healthy' food, according to a new study in the Journal of the American Medical Association. In this report, Harvard researchers say that a fish meal even once a month may offer men some protection from a common form of stroke.

A close look at diet

The researchers assessed the fish intake of more the more than 43,000 participants of the Health Professionals Follow-Up Study several times over an 8-year period. They then kept track of the men for an additional 4 years and noted the number who suffered a stroke at any time during the 12-year study.

After accounting for factors that affect the risk of stroke - including weight, smoking status, use of aspirin, and history of hypertension - they found that the study participants who ate fish at least once a month were about 40% less likely than those who rarely ate fish to suffer an ischemic stroke, the type of stroke caused by a blockage of blood flow to the brain.

What makes fish so good for you?

Fish, especially the cold-water varieties, are good sources of omega-3 fatty acids. Scientists believe that this type of fatty acid makes blood cells less likely to stick together. This reduces the chance that a blood clot will block blood flow to the heart - triggering a heart attack - or to the brain, resulting in ischemic stroke.

Note that, even though the men in this study who ate fish only a couple of times a month were better off than those who ate it less frequently, this falls short of current recommendations from the American Heart Association (AHA). The AHA believes that consumers will get the greatest heart health benefit from omega-3s by eating fish at least twice a week.

Where to get your omega-3s

Omega-3 fatty acids cannot be manufactured by the body, so you have to get them from your diet. Cold-water fish like salmon, tuna, mackerel, and herring are particularly good sources of omega-3s, but most varieties of fish contain some. In addition, flaxseed, canola and soybean oils, as well as some nuts and seeds contain a fatty acid that can be converted by the body into a usable form of omega-3s.

What about supplements?

Fish oil supplements - which deliver a concentrated dose of omega-3s - did not appear to reduce stroke risk in this study, but the authors say that there may have been too few participants taking the supplements for them to draw a proper conclusion.

If you're considering bypassing fish altogether in favor of fish oil supplements, talk to your physician first. These capsules can deliver doses of omega-3s much higher than would normally be found in foods. And because omega-3s can make the blood less likely to clot, high doses could do more harm than good.

Source

• Fish consumption and risk of stroke in men. K. He, E. Rimm, A. Merchant,  et al., JAMA, 2003, vol. 288, pp. 3130--3136

Related Links
Omega-3's, the Heart Healthy Fat
Food Shopping? Add Fish to Your List
What's the Best Diet For Preventing Heart Disease?
To quickly access additional accurate information on this and other nutrition-related topics, visit Tufts University's Nutrition Navigator

Please take a moment to give us your comments. For questions about Health matters you may check our "Questions & Answers" Portal and Service.