The use of artificial sweeteners has increased dramatically in recent decades.
At the same time, obesity rates have skyrocketed. However, the link between artificial sweetener use and obesity is controversial.
A new study was just done that examines the use of artificial sweeteners in pregnancy and the risk of obesity in child.
The findings were very interesting, and are outlined below.
More than 30% of pregnant women may regularly consume artificially sweetened beverages.
Animal studies suggest that when unborn offspring are exposed to artificial sweeteners they are more likely to develop overweight or obesity after birth.
They also tend to have greater preferences for sweet foods, changed blood lipid profiles and increased insulin resistance.
However, until now, this association has never been examined in humans.
This study assessed the consumption of artificial sweeteners among pregnant mothers and examined its association with infant body mass index.
This was an observational cohort study examining the link between maternal consumption of artificial sweeteners and infant obesity.
It included 2686 healthy, pregnant women from the Canadian Healthy Infant Longitudinal Development (CHILD) Study.
The dietary intake of these women was estimated using a food frequency questionnaire during the second or third trimester of pregnancy.
One year after birth, the researchers measured the body mass index (BMI) of their children.
Bottom Line: This observational study examined the association of artificial sweetener intake among pregnant mothers and infant body mass index at age one.
Finding: Maternal Consumption of Artificial Sweeteners Was Linked With an Increased Risk of Infant Overweight
More than a quarter of the women in this study consumed artificial sweeteners during pregnancy.
At one year of age, the children of those women who consumed a lot of artificial sweeteners during pregnancy had a higher body mass index (BMI) than those who consumed less.
Additionally, they were twice as likely to be overweight at age one, compared to those who weren’t exposed to artificial sweeteners while still in the womb.
Infants of women who consumed artificially sweetened beverages were 119% more likely to be overweight at 1 year, compared to women who consumed them less than once per month.
When the analysis was done separately for each gender, the researchers found that maternal intake of artificial sweeteners was only linked with body weight in boys. This is supported by a study in mice.
These associations remained significant even after adjusting for maternal BMI, diet quality, total calorie intake and other risk factors for obesity.
Bottom Line: The study showed that high intake of artificial sweeteners among pregnant women increased their child’s risk of becoming overweight or obese at age one. However, the association was only significant in boys.
Do Artificial Sweeteners Really Cause Weight Gain?
This was the first human study to suggest that maternal consumption of artificial sweeteners during pregnancy may increase the risk of weight gain and obesity in the infant.
A few observational in humans have also suggested that artificial sweeteners may increase the risk of weight gain and metabolic syndrome in adults.
However, these were all observational studies, meaning that they couldn’t demonstrate a cause-and-effect relationship.
Their results have also been inconsistent, with some studies suggesting that artificial sweeteners may reduce the risk of obesity.
Additionally, a recent meta-analysis of randomized controlled trials concluded that low-calorie sweeteners reduce calorie intake and body weight. This is discussed in a previous research review.
Bottom Line: Human studies haven’t proved that artificial sweeteners promote weight gain. Observational studies have provided inconsistent results.
How Might Artificial Sweeteners Cause Weight Gain?
Researchers have come up with several ideas of how eating artificial sweeteners could affect body weight in adults.
- Changes in glucose metabolism.
- Disruption of the gut microbiota.
- Dysregulation of appetite control and calorie compensation.
Since artificial sweeteners have been detected in human breast milk, infants may be exposed to sweeteners consumed by their mothers.
Bottom Line: Several theories have been proposed to explain the possible effects of artificial sweeteners on body weight. These involve adverse changes in glucose metabolism or the gut microbiota.
The main limitation of this study is its observational design.
Second, the study didn’t distinguish between different types of artificial sweeteners, and didn’t account for the amount found in solid foods.
Third, the researchers assessed the intake of artificial sweeteners using food frequency questionnaires (FFQ). Although they are generally good at differentiating between high and low consumers, FFQs are often inaccurate.
Additionally, the questionnaire used in the present study was not specifically validated for beverages.
Finally, infant overweight and obesity were estimated using BMI, which is an inaccurate measure of body fat.
Bottom Line: The study’s main limitation was its observational design. Measures of artificial sweetener intake and body fat were also inaccurate.
Summary and Real-Life Application
In short, this study suggests that high intake of artificial sweeteners among pregnant women may increase their children’s risk of excessive weight gain and obesity.
However, since the study had an observational design, it couldn’t prove that artificial sweeteners were responsible for the association.
For this reason, the role of artificial sweeteners in infant weight gain and obesity are still unclear. Randomized controlled trials are needed before any hard conclusions can be reached.