Artificial sweeteners cause “toxic effects” on gut microbes, study says

03 Oct 2018 --- Artificial sweeteners have again come in the spotlight after a paper published in Molecules claimed that US FDA-approved artificial sweeteners and sports supplements were found to be toxic to digestive gut microbes. In response, the International Sweeteners Association (ISA) reiterates that all approved low-calorie sweeteners are among the “most thoroughly researched ingredients worldwide,” and put forward that the in vitro testing conditions could have caused some reactions that would not be seen with real-life exposure conditions.

The collaborative study by researchers at Ben-Gurion University of the Negev (BGU) in Israel and Nanyang Technological University in Singapore indicated relative toxicity of six artificial sweeteners (aspartame, sucralose, saccharine, neotame, advantame and acesulfame potassium-k) and ten sports supplements containing these artificial sweeteners.

According to the researchers, the gut bacteria became toxic when exposed to concentrations of only one mg./ml. of the artificial sweeteners.

“We modified bioluminescent E. coli bacteria, which luminesce when they detect toxicants and act as a sensing model representative of the complex microbial system,” says Professor Ariel Kushmaro, John A. Ungar Chair in Biotechnology in the Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, and member of the Ilse Katz Institute for Nanoscale Science and Technology and the National Institute for Biotechnology in the Negev.

“This is further evidence that consumption of artificial sweeteners adversely affects gut microbial activity which can cause a wide range of health issues,” he adds.

Artificial sweeteners are used in countless food products and soft drinks with reduced sugar content. Many people consume this added ingredient without their knowledge. Moreover, artificial sweeteners have been identified as emerging environmental pollutants and can be found in drinking and surface water, and groundwater aquifers.

“The results of this study might help in understanding the relative toxicity of artificial sweeteners and the potential of negative effects on the gut microbial community as well as the environment. Furthermore, the tested bioluminescent bacterial panel can potentially be used for detecting artificial sweeteners in the environment,” says Kushmaro.

In response, ISA reiterates that all approved low-calorie sweeteners are among the “most thoroughly researched ingredients worldwide.”

“Before being approved to be used on the market, low calorie sweeteners must undergo a thorough safety assessment by the competent food safety authority, such as the Joint Expert Scientific Committee on Food Additives (JECFA) of the United Nations Food & Agriculture Organization (FAO) and the World Health Organization (WHO), the US Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA). Based on extensive testing and a strong body of scientific evidence, regulatory food safety bodies around the world consistently confirm their safety,” a spokesperson to ISA tells NutritionInsight.
 
“The study by Harpaz et al. does not provide evidence that low-calorie sweeteners can be toxic to digestive gut microbes in humans. Indeed, these findings resulted from an in vitro experiment, which exposed bacteria to different concentrations of low-calorie sweeteners out of the human body. It is important to mention that the in vitro testing conditions could have caused reactions that would not be seen with real-life exposure conditions in humans,” the ISA spokesperson adds. “A strong body of well-designed and robust studies conducted in vivo, in both animals and humans, have confirmed that low-calorie sweeteners are safe and not toxic.”