The Surprising Possible Cause Of An Early First Period

Photographed by Rockie Nolan.
Girls are starting to hit puberty earlier and earlier — which means they're getting their periods at younger ages. Now, new research suggests that what we drink might be a factor in when we first experience that crimson tide.

The study, recently published online in the journal Human Reproduction, looked at data from 5,000 girls between the ages of nine and 14, starting in 1996. Initially, the participants all filled out questionnaires about their dietary habits and whether or not they had started their periods. Five years later, the investigators checked in to see if anything had changed.

They found a link between the average amount of sugar-sweetened drinks (such as sodas, fruit drinks, and iced teas) the participants consumed and when they were most likely to start their periods. In particular, girls who gulped down more than 1.5 sugary drinks per day got their periods an average of 2.7 months earlier than those who had less than two servings of the sugary stuff in a week. Of course, this study was correlational, so we don't necessarily know that sugary drinks cause an earlier first period.

Still, previous research has suggested there may be some undesirable effects from getting your first period early (before the age of 10), such as a heightened risk for cardiovascular disease. And, the younger you are when you get your first period, the higher your risk for breast cancer. This study's authors suggest that consuming a lot of sugar-sweetened drinks could have a "modest" impact on that risk.

However, this research is confounded by the effects of obesity, which can also influence the start of menstruation — and is associated with higher risks for developing both heart disease and breast cancer. In this study, investigators tracked this connection with the (admittedly imperfect) measure of BMI, finding that higher BMI correlated with earlier periods in the same way that drinking sugary beverages did. So, the authors suggest that obesity could be one mediating factor between sugar-drinking habits and participants' first-period ages.

Just one of many reasons to keep our sugary drink-consumption in check (you don't even want to know how much walking it takes to work off one of those things).

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