A study, conducted by JAMA Pediatrics, found the first human evidence that the consumption of artificial sweeteners during pregnancy causes an increase in infant body mass index (BMI).

Childhood obesity rates have doubled in the past 30 years, leaving one-third of children in developed countries overweight or obese. Animal studies have previously shown that consumption of artificial sweeteners while pregnant may predispose offspring to develop obesity, but these findings have not been tested on human subjects before.

“Added sugar intake is strongly associated with obesity and related comorbidities, prompting population-wide recommendations to reduce sugar consumption. As a result, sugar replacements or nonnutritive sweeteners (NNSs) have become increasingly popular, with more than 50% of Americans reporting NNS consumption in recent surveys and cohort studies," wrote Meghan B. Azad, PhD, and colleagues. “Although few data are available for pregnant women in the United States, cohort studies from Norway and Denmark have found that more than 30% of women report consuming artificially sweetened beverages during pregnancy. Despite the widespread and increasing consumption of NNSs, their long-term effect on human health is poorly understood, and current intake recommendations are unclear, particularly for pregnant women and young children.”

The goal of this study was to determine whether maternal consumption of artificially sweetened beverages during pregnancy is associated with infant BMI.

The study analyzed 3,033 mother-infant couples from the Canadian Healthy Infant Longitudinal Development (CHILD) study, a population-based birth cohort that recruited healthy pregnant women from 2009 to 2012. Women were given food frequency questionnaires in the second or third trimester of pregnancy and their infants’ BMI’s were calculated according to the 2006 World Health Organizations standards at 1 year of age. Measurements were taken for both artificially sweetened beverages and sugar-sweetened beverages

The results showed that of the 3,033 pregnant women studied, 29.5 percent consumed artificially sweetened beverages, including 5.1 percent who reported daily consumption. Compared to those who did not consume artificially sweetened beverages, infants born to women who consumed artificially sweetened beverages had a 0.20-unit increase in infant BMI and a two-fold higher risk of an infant to be overweight at 1 year old.

With these results, the first on human subjects, evidence shows a clear correlation to metabolic diseases being acquired or “programmed” in early life. With studies now on both animal and human subjects, the offspring of mothers with higher caloric intake are at a higher risk of developing to be overweight and obese later in life. Interestingly, studies have shown that consumption of sugar-sweetened beverages had no comparable associations to data concluded by the consumption of artificially sweetened beverages.

“To our knowledge, we provide the first human evidence that maternal consumption of artificial sweeteners during pregnancy may influence infant BMI,” wrote Azad and colleagues. “Given the current epidemic of childhood obesity and widespread use of artificial sweeteners, further research is warranted to confirm our findings and investigate the underlying biological mechanisms, with the ultimate goal of informing evidence-based dietary recommendations for pregnant women.”