It's no secret that sugary beverages like soda aren't the greatest dietary choice. But the latest mark on their record has nothing to do with calories or cavities, as sweetened drinks are now being linked to earlier periods in young girls.
According to a new study, which was published in the online journal, Human Reproduction, girls who drank one-and-a-half 12-ounce cans a day of non-diet soda or sugared iced tea had their first menstrual cycles an average of 2.7 months earlier than those who consumed less than two cans a week. And among the 5,583 girls, ages 9 to 14 who participated by filling out diet questionnaires yearly from 1996 to 1998, those who consumed the most sugary drinks started menstruating at 12.8 years of age, compared to 13 years for those drinking the least.
This effect was independent of birth weight, their mother's age at first period, physical activity, and other dietary and behavioral factors, all of which were controlled for by the researchers. Lead author and associate professor of epidemiology at Harvard, also notes that the connection was independent of the well-known link between obesity and earlier onset menstruation cycles.
"Our findings our robust and not dependent on body mass index," she says. "Sugared beverages are not healthy to begin with, and there should be heightened attention to avoiding them."
And considering girls who get their periods at younger ages have a slightly greater risk of breast and endometrial cancer later in life, that certainly makes sense. Additionally, more recent studies have shown women who started menstruating before age 10 (or after age 17, for that matter) have a greater risk for heart disease, stroke, and other issues related to high blood pressure.
So while a 2.7 month decrease may not seem significant, the study's lead author and Harvard's School of Public Health epidemiologist Jenny Carwile insists the findings are important on a population level.
"They (the findings) are actually very powerful because consumption of these kinds of drinks is something that can be modified," she says.