The study, published in JAMA Pediatrics, analysed data from more 3,000 mother-infant pairs and found that daily consumption of artificially sweetened beverages, such as diet sodas, is associated with increased infant body mass index (BMI) and a doubling in the risk of being overweight in early childhood.
Led by Dr Meghan Azad from the University of Manitoba in Canada, the research team noted that given the dramatic increase in consumption of artificially sweetened drinks in the general population, including pregnant women, as well as recent animal data that has linked maternal consumption to obese offspring, it was important to explore potential links in human mother-infant pairs.
"To our knowledge, our results provide the first human evidence that artificial sweetener consumption during pregnancy may increase the risk of early childhood overweight,” wrote the researchers.
“Maternal consumption of artificially sweetened beverages during pregnancy was significantly associated with infant body mass index at 1 year of age,” they said. “After controlling for maternal obesity and diet quality, daily artificially sweetened beverage consumption was associated with a 0.2-unit increase in infant body mass index z score and a 2-fold higher risk of overweight.”
Preliminary findings that warrant further work
Writing in an accompanying editorial for the same journal, Dr Mark Pereira from the University of Minnesota and Dr Matthew Gillman of Harvard Medical School, suggest that despite the caveat that the current observational study cannot show causation, the findings warrant further research.
“The findings of Azad et al remind us that ASBs yield uncertain benefits for the mother and raise the prospect of risk for her child,” they wrote. “However, we view the findings … as preliminary.”
Furthermore, Pereira and Gillman noted that previously suggested potential mechanisms of action, such as the ‘sweet-but-no-calories mechanism’ are unlikely to apply because the infant is not the beverage drinker, whilst any microbiome-related mechanism is ‘speculative’.
“Other mechanisms, which would need to account for how maternal consumption of ASBs is transduced into an obesogenic tendency in the foetus, are not apparent,” they said.
The team analysed data from 3033 mother-infant pairs from the Canadian Healthy Infant Longitudinal Development (CHILD) Study, a population-based birth cohort that recruited healthy pregnant women from 2009 to 2012.
As part of the study, women completed dietary assessments during pregnancy, and their infants’ BMI was measured at one year of age.
Azad and her colleagues reported that compared with no consumption, daily consumption of artificially sweetened beverages was associated with a 0.20-unit increase in infant BMI score and a doubling in the risk of infant overweight at one year of age.
“These effects were not explained by maternal BMI, diet quality, total energy intake, or other obesity risk factors,” noted the team. “There were no comparable associations for sugar-sweetened beverages.”
The authors concluded that further research is now needed to confirm the findings and investigate the underlying biological mechanisms, “with the ultimate goal of informing evidence-based dietary recommendations for pregnant women.”