Researchers studied the effect of coffee drinking on the risk for rosacea, a chronic skin disease that causes facial redness in about 5 percent of the population. The scientists used data on 82,737 women participating in a large health study between 1991 and 2005.

The analysis, in JAMA Dermatology, found that compared with women in the lowest one-fifth for caffeinated coffee consumption, those in the highest one-fifth were 24 percent less likely to have rosacea. Women who drank four or more cups a day had a 23 percent lower risk of the skin disorder than those who drank less than a cup a month.