Photo

Drinking diet soda and other artificially sweetened beverages during pregnancy is associated with having overweight 1-year-olds, according to a new report.

Canadian researchers studied 3,033 mothers who delivered healthy singletons between 2009 and 2012 and had completed diet questionnaires during their pregnancies. They then examined the babies when they were a year old. Almost 30 percent of the women drank artificially sweetened beverages during pregnancy.

After controlling for maternal body mass index, age, breastfeeding duration, maternal smoking, maternal diabetes, timing of the introduction of solid foods and other factors, they found that compared with women who drank no diet beverages, those who drank, on average, one can of diet soda a day doubled the risk of having an overweight 1-year-old.

The study, in JAMA Pediatrics, found no association with infant birth weight, suggesting that the effect is on postnatal, not fetal, growth. The mother’s consumption of sugar-sweetened drinks was not associated with increased risk for overweight babies.

“This is an association, and not a causal link,” said the lead author, Meghan B. Azad, an assistant professor at the University of Manitoba. “But it certainly raises the question of whether artificial sweeteners are harmless. It’s not time to ban them or tell everyone not to consume them, but there’s no great benefit to consuming these drinks, so there’s no harm in avoiding them.”