Menstruation may come earlier for girls who have a habit of guzzling down gallons of soda pop every week, according to a Harvard study, in which researchers conducted a long-term survey to explore a possible link between the timing of puberty and sugar-induced metabolism changes. Lead researcher and senior study author, Karin Michels of Harvard Medical School’s obstetrics, gynecology and reproductive biology department explains that while the results establish a correlation between the consumption of sugary drinks and the onset of first menstruation, they cannot prove a definitive causal relationship or explain the inner workings at the root of the connection. The significance of the nominal difference in the average age at which a young girl starts her period is not clear, yet some possible risks are easily avoidable with a simple change in habits of drinking sugar-sweetened beverages.
The research team followed 5,583 nine to 14 years old girls who had not yet started to menstruate, for five years, between 1996 to 2001. They controlled for height but not body mass index (BMI). The girls self-reported their food intake and sugary drink consumption on a detailed annual survey that allowed scientists to isolate sugar intake from the drinks alone versus other foods. After analyzing the result, the researchers found that those who reported drinking 1.5 servings or more of sugary drinks every day started menstruation 2.7 months earlier than those who limited their intake to twice a week or less. The average age of the onset of puberty was 12.8 years for those with the strongest sugary drink habits and 13 years for those with more moderate sugar habits. The correlation did not extend to those who drank fruit juices, sweetened ice teas and diet sodas, however. The paper was published in the Human Reproduction Journal online on Jan. 28, 2015.
The reason for the apparent correlation is not entirely clear, researchers admit, although sugar is known to have metabolic effects that could possibly have repercussions on the timing of the girls’ first periods. The study also concedes that they did not account for sugary beverage consumption in early childhood so they cannot draw any conclusions about how early exposure may skew the results. Therefore, they recognize that more study is necessary to make a clear-cut determination of the link between first menstruation and the frequency and quantity at which the girls drink sugary beverages such as soda pop, sweetened teas and fruit drinks.
Michels explains that the higher glycemic index of artificially sweetened drinks cause an insulin spike, which may stimulate sex hormones that trigger the menstruation cycle. Nonetheless, the scientific team that conducted the study is uncertain of its true implications in terms of the effect on pre-teen and teen girls’ health. Although, there is some speculation about a possible “modest impact” on the risk of breast cancer, leading the study’s first author, Jenny Carwile to take a cautious position in suggesting that the results hammer another nail into the coffin of children’s consumption of soda pop.
Furthermore, she points out that early menstruation increases the risk of teenage depression and breast cancer later in life, not to mention the established link of sugary drinks and weight gain. Given the lack of nutritional value contained in soda pop and other sugar drinks, nutritionist Samantha Heller of New York University Langone Medical Center agrees with Michels that the study underscores the counsel of many dietitians, suggesting that no amount of justification or reasoning warrants condoning excessive consumption of sugary drinks and soda pops. They argue that regardless of whether the link to early menstruation passes further scrutiny and holds up to additional testing, there is no reason to play games with chance in regards to health risks as serious as breast cancer and long term mental health.
By Tamara Christine Van Hooser