There are many good reasons to avoid drinking sweetened beverages. Here is another: A large study has found an association between drinking sugary beverages and a younger age at first menstruation in girls in the United States. This is important because an early onset of menstruation, called menarche, is associated with a higher risk of breast cancer later in life.
The study followed nearly 5,600 girls aged 9 to 14 who had not had their first period when they entered the study between 1996 and 2001. They were asked to complete a questionnaire each year that included questions asking how often they drank sugar-sweetened beverages, which included fruit drinks, sugar-sweetened soda, and noncarbonated sweet drinks like lemonade and iced tea. The sugar ingredients in these drinks included sucrose, glucose, and corn syrup.
The researchers found that girls who drank more than 1.5 servings of sugar-sweetened drinks per day had their first period 2.7 months earlier than those who drank only 2 servings of sugary beverages a week. A serving size was 12 ounces. The study controlled for other factors including body mass index, height, total food intake, and how much physical activity the girls got.
The study found that diet sodas and fruit juice were not associated with any change in age at menarche.
Sugary beverages play a role in childhood obesity and girls who are overweight or obese often start menarche earlier. However, this study controlled for body mass index and still found an association between sugary drinks and earlier menarche.
A reduction of 2.7 months in a girl's age at menarche will probably not have a large impact in her long-term health. However, unlike most other predictors of menarche, drinking sugary beverages is a factor that can be changed.
The girls were part of the Growing Up Today Study, which follows the children of women who are enrolled in the very large and ongoing Nurses' Health Study II. This study was published in the journal Human Reproduction.