Extra pounds may not doom hypertensive patients.

Physicians often tell older, overweight patients that losing a few pounds is crucial to their health, particularly if they have high blood pressure. However, a 20-year study of more than 90,000 older, hypertensive veterans suggests that, for some people, extra weight isn't as dangerous as most doctors assume.

In the study, led by H. Mitchell Perry Jr., a hypertension specialist at Washington University School of Medicine in St. Louis, obesity only slightly raised the risk of death and heart attacks and it had no effect on stroke. In fact, those who were at or just below their "desirable" weights were more likely than extremely obese patients to die within 20 years.

The study involved 90,070 veterans who were diagnosed with hypertension in the mid 1970s at Veterans Administration clinics across the country. The subjects were 95% male, 35% black, and generally low-income. The mean age when treatment began was 51.

The researchers separated the patients into seven groups based on initial body-mass index (BMI), a measure that relates weight to height. For instance, a 5'10" person weighing 193 pounds would have a BMI of 28, which, for men, generally is considered the lower limit for being overweight.

A little extra weight seemed to be a blessing. Patients who were moderately overweight (BMI 27-34) had the best chance of being alive after 20 years. In comparison, those who were extremely obese (BMI more than 38) were 30% more likely to die during that time.

While severe obesity was indeed dangerous, another, thinner group fared even worse. Patients with BMIs between 19 and 23 were 40% more likely to die in 20 years, compared with the slightly overweight group. These high death rates for this population differ from the findings of the National Institutes of Health, which says that the healthiest BMI for the average American man is between 22 and 24. According to patient questionnaires, subjects in Perry's study in the "healthy" weight range were more likely than their heavier counterparts to drink heavily and smoke.

The picture was even bleaker for the thinnest group...