Eating Fish = Healthy Heart in Diabetes

March 31, 2003 -- Eating fish regularly is believed to reduce the risk heart disease events like heart attack and stroke in healthy people. Now new research suggests it may be particularly protective against heart disease in women with diabetes.

Women with type 2 diabetes who ate fish once a week were 40% less likely to develop heart disease than those who rarely ate it, and eating fish almost every day was associated with a two-thirds reduction in risk. The women who ate more fish also tended to eat less red meat and more fruits and vegetables, but this and other studies point to a direct protective benefit for eating seafood, says researcher Frank B. Hu, MD, of the Harvard School of Public Health.

"This provides strong evidence that fish consumption is beneficial," says Hu, who is one of the nation's leading investigators of nutrition and disease risk. "Eating fish should be strongly recommended for people with diabetes."

The American Heart Association (AHA) currently recommends that adults, with the exception of pregnant women, eat at least two servings of fish each week. It is believed that omega-3 fatty acids abundant in the fat of many fish reduces the risk of heart disease by lowering triglyceride levels, improving blood vessel function, and reducing blood-clot formation.

But AHA spokeswoman Alice H. Lichtenstein, DSC, says even though studies like this one are impressive, they do not prove that eating fish alone will ward off heart disease. That is because most are observational, meaning they rely on participant recall. Lichtenstein is a professor of nutrition at Tufts University.

"People who eat a lot of fish also tend to lead healthier lifestyles in general," Lichtenstein tells WebMD. "Even though these studies try to control for lifestyle factors, it is very difficult to do this. So we can't really say how protective fish consumption is."

The latest research, to be published April 15 in the AHA journal Circulation, included some 5,100 women with type 2 diabetes taking part in the ongoing Nurses' Health Study. Having diabetes is one of the leading risk factors for heart disease.

The women were divided into five categories according to how often they ate fish, with the lowest consumers eating fish less than once a month and the highest eating it five times a week or more. Compared with those who seldom ate fish, eating seafood one to three times a month was associated with a 30% reduction in risk. A risk reduction of 40% was seen in those eating fish once a week, and those who ate fish two to four times a week had a 36% reduction in risk. The biggest risk reduction --64% -- was seen in women who ate fish five times a week or more.