Zero-Calorie Sweetener Study Has Bad News For Nursing Mothers

A new study raises questions over whether zero-calorie sweeteners are safe for expecting and nursing mothers. The research, which was recently published in the journal Frontiers in Microbiology, found that two common zero-calorie sweeteners given to pregnant and nursing mice caused harmful gut bacteria and metabolic changes in their pups. Small amounts of these sweeteners can be passed to pups in breast milk and via the placenta.

Zero-calorie sweeteners offer multiple benefits, the most obvious being the lack of calories. These products are popular among dieters, diabetics, and anyone looking to reduce their sugar consumption, but they aren't without controversy. Past research has indicated these sweeteners may still cause inflammation and an insulin response in the people who consume them, negating some of the benefits.

Researchers behind this latest study point out that while zero-calorie sweeteners may be safe in moderation, they're not necessarily a healthy alternative to sugar. The team looked at the potential health effect in offspring born to mothers that consumed the popular sweeteners sucralose and acesulfame-K.

A total of 226 mouse pups were studied, confirming that both aforementioned sweeteners can be passed on to the pups in the womb and while nursing. The mice were fed a mixture of both sweeteners during pregnancy through the lactation period. One group of mice received the acceptable daily intake (ADI) of both sweeteners, while another group received double the ADI. A separate control group was given water.

READ: Heating food sweetened with sucralose may be harming your health

Pups born to mothers from both the ADI and double ADI groups were found to experience 'significant metabolic changes' despite low overall exposure to the sweeteners. The changes, according to the study, pointed toward an impairment of the body's ability to remove toxins from the blood.

The pups also experienced a 'dramatic shift' in gut bacteria. Pups from both groups were found to have suffered loss of Akkermansia muciniphila, a highly beneficial gut bacteria species. The researchers note that when these gut bacterial changes have been found in humans, they were linked with obesity and type 2 diabetes.

Though negative effects were found in both the ADI and double ADI groups, the latter group (which received double the daily intake limit) also experienced lower fasting glucose levels, lower weight, and greater metabolic changes. Gut bacteria changes were a big exception, with more drastic alternations noted in the ADI group.

The sweetener saccharin should be entirely avoided during pregnancy, but other artificial sweeteners are generally considered safe when used in moderation. These zero-calorie sweeteners can be found in a large number of products, including beverages and items one may not immediately consider, such as toothpaste and mouthwash.

The researchers point out that it can be difficult for consumers to monitor how much artificial sweetener they're consuming daily, meaning it's possible to go over the daily recommended intake limit without realizing it. Based on the findings of this study, which focused on mice, the researchers explained that zero-calorie sweeteners should be looked into for their potential effect on human development.