Fish dishes may catch on among smokers.

Dining on fish on a regular basis may serve smokers well, researchers suggest.

A study of 4,928 former smokers and 4,032 smokers, all age 45 to 64, indicates that the more fish the volunteers ate, the lower their likelihood of having lung disease. Dark-meat fish, such as salmon and bluefish, have the highest concentrations of the protective n-3 polyunsaturated fatty acids, scientists report in the July 28 NEW ENGLAND JOURNAL OF MEDICINE.

Compared to participants who reported rarely eating fish, the volunteers who ate seafood most often -- about four times a week -- had half the incidence of chronic obstructive pulmonary disease (COPD), says coauthor Eyal Shahar of the University of Minnesota School of Public Health in Minneapolis. The 1,000 volunteers with COPD had at least one of the following conditions: chronic bronchitis, emphysema, or reduced lung function, as measured by a spirometer.

Although the study does not prove that eating fish protected the smokers, it makes a good case for more research on the relationship between fish consumption and COPD, says Shahar. In epidemiological research, he notes, "it's almost surprising to find such a strong correlation as we have."

Gary W Hunninghake of the University of Iowa College of Medicine in Iowa City agrees. He describes the findings as "highly suggestive" of an association between how much fish smokers eat and their risk of COPD.

However, the investigators detected no such correlation for the 1,674 black volunteers. "We are uncertain why," they write, but they suggest that there may have been insufficient data on blacks to find an association.

Other research boosts the argument that fish may help protect against the damage cigarette smoking inflicts, says Shahar. For instance, scientists know that smoking can lead to the chronic inflammation of the lungs that characterizes COPD, and studies have shown that large doses of n-3 fatty acids interfere with the body's inflammatory response.

Nonsmokers who suffer f rom occasional bouts of bronchitis need not rush to the fishmonger because of this study Shahar says. In fact, the findings have "no implication for nonsmokers," he contends, adding that their bronchitis differs significantly from that of smokers.

Nor do these findings let fish-loving smokers off the hook. "I don't want this [research] to cause people to say, 'Yea! I can smoke and eat fish.' This is my worst nightmare," says Shahar, whose father died of smoking-related lung cancer.