The studies, published in the July issue of Alcohol: Clinical Experience and Research, found that men who had as few as one or two glasses of alcohol on a regular basis had a much higher incidence of hypertension than those who did not drink at all.
Several U.S. studies have found that moderate drinking habits can actually decrease the risk of heart disease. American studies have also found that regular alcohol consumption does not affect hypertension risk below a threshold of three to six drinks.
Two general differences between Japanese and American populations may help explain the aberrant findings of these studies.
First, there is significantly more obesity in the United States than in the Japanese population. A higher blood-alcohol level can be expected in a lower-weight population at similar drinking levels, potentially resulting in a lower threshold effect.
Second, about 50 percent of Japanese people have a genetic defect that affects the metabolism of alcohol. However, recent studies of this defect have found no effect on risk of hypertension.
In the first Japanese study, Susumu Ohmori, M.D., and colleagues at Kyushu University found that up to a point, the incidence of hypertension rose with the amount of alcohol men drank.
Ex-drinkers, who had not had a drink within three months, were still nearly twice as likely to develop hypertension as men who did not drink at all. Those who drank a moderate amount on a regular basis had an even higher incidence and those who had more than a couple of drinks a day had about a threefold higher incidence of high blood pressure than non-drinkers.
The study included 1,101 residents of Hisayama Town, a suburban community. The researchers studied the subjects over a 10-year span. The study included men and women, but the heightened risk of hypert
Contact: Noriyuki Nakanishi
Center for the Advancement of Health