Study suggests drinking soda in pregnancy affects kids’ weights

Here’s another guilty pleasure that pregnant women may be told to give up: soda and other sugary beverages.

The children of mothers who consumed sugary drinks during their second trimester had a higher weight status than children of mothers who avoided the beverages, according to a study by Massachusetts researchers published Monday in the journal Pediatrics. For each additional serving per day, the child would weigh about half a pound more by age 8.

The study followed 1,078 pairs of mothers and children from a prebirth study called Project Viva, which received National Institutes of Health funding. The study began in 1999 and will follow up with participants next when they are 16 to 17 years old.

“I was surprised by [the fact that] maternal intake seemed to be more important than child intake” when it comes to sugary drinks, said Sheryl Rifas-Shiman, coauthor of the study and a biostatistician at Harvard Medical School and the Harvard Pilgrim Health Care Institute. She said that the researchers controlled for the children’s intake of sugary beverages in mid-childhood and found that the associations between the mom’s intake and the child’s body mass index remained.

“In our study it seemed like mom’s intake was related to obesity no matter what the kids’ intake was,” Rifas-Shiman said. “As an important next step, we’re going to be looking at the timing of the kids’ intake.”

The study did not find a link between mothers’ sugary beverage intake during the first trimester and her child’s weight. The researchers believe this may have to do with the fact that fetal fat accumulation accelerates during the second trimester, though the study did not directly test this.

Mothers answered periodic questionnaires about their beverage intake in the study.

Jonathan Davis, chief of newborn medicine at the Floating Hospital for Children at Tufts Medical Center, said that a follow-up study might try to get mothers to record their daily intake more regularly.

“These kinds of studies are done by parents recalling — a mother recalling what she ate and how many of these drinks she had,” he said, noting that this leaves room for errors in judgment and recall.

Davis highlighted the importance of tackling childhood obesity, which increases the risk of diabetes, asthma, and other diseases.

“It goes from one generation to the next,” he said.

Rifas-Shiman’s advises women who are pregnant that “avoiding high intake of sugary beverages during pregnancy could be one of several ways to prevent childhood obesity.”