BODY

Age of first menses has decreased substantially since the early 20th century, and studies have shown that younger age of menarche is associated with increased risk of breast and endometrial cancer in later life.Here is another mark against sugary drinks: A new study has found that drinking them is associated with lowered age of menarche.

By NICHOLAS BAKALAR

The study, published online in Human Reproduction, used data on 5,583 girls ages 9 to 14 who had not yet attained menarche at the start. They filled out diet questionnaires yearly from 1996 to 1998. By 2001, 159 still had not yet had their first period.

After controlling for birth weight, maternal age at menarche, physical activity, and many dietary and behavioral factors, they found that girls who drank one-and-a-half 12-ounce cans a day of nondiet soda or sugared iced tea had their first period an average of 2.7 months earlier than those who drank less than two cans a week.

The lead author, Karin B. Michels, an associate professor of epidemiology at Harvard, said that the contribution of sugary drinks to early menarche was independent of the well-known contribution of obesity.

“Our findings are robust,” she said, “and not dependent on body mass index. Sugared beverages are not healthy to begin with, and there should be heightened attention to avoiding them.”