RESEARCH ALERT: Artificial Sweeteners Significantly Alter the Small Bowel Microbiome
FINDINGS
Cedars-Sinai investigators examined the potential effects of consuming non-sugar sweeteners, including both non-aspartame non-sugar sweeteners and aspartame alone, on the composition of the stool and duodenal microbiomes. Compared to controls in the study, scientists noted significant differences in both stool and duodenal (small intestine) microbial diversity and composition. Levels of circulating inflammatory markers were also altered in participants who consumed non-aspartame non-sugar sweeteners as well as those using aspartame only.
BACKGROUND
More than 140 million people in the United States use sugar substitutes, according to data from the U.S. Census Bureau. Sucralose, aspartame, saccharin and the plant-based stevia leaf extract are among the most popular. These artificial sweeteners are frequently used by people trying to reduce their sugar intake or lower calories from sugar for weight management. But there are increasing concerns about the potential health risks associated with the use of non-sugar substitutes based on data suggesting they do not help with long-term weight loss and may be linked to higher risks for Type 2 diabetes, heart disease and death. There are also questions about the potential negative effects the sugar substitutes may have on the gut microbiome, which plays a vital role in overall health.
In a controlled study, Cedars-Sinai investigators analyzed and compared the duodenal luminal microbiome in subjects consuming artificial sweeteners, aspartame alone or no sugar substitutes. The stool microbiome in some of these subjects was also compared.
METHOD
Investigators obtained samples from a small group of adults undergoing standard of care esophagogastroduodenoscopy without colon prep. All enrolled subjects provided duodenal luminal aspirates as well as fasting blood samples for analysis, and a subset also provided optional stool samples. Scientists analyzed the duodenal luminal microbiome in subjects consuming non-aspartame non-sugar sweeteners (NANS, N=35), aspartame only (ASP, N=9), and controls (CON, N=55), and the stool microbiome in a subset (N=40).
IMPACT
Artificial sweeteners are associated with a variety of changes depending on the area of the intestine. Significantly, the effects of these substances on the gut microbiome differ in the small bowel compared to the large bowel. These changes may be potentially important for health and warrant future study.
JOURNAL
The study is published in the journal iScience.
EXPERT COMMENTARY
“Artificial sweeteners are not benign for the microbiome of the gut. We found that the richness of the bacteria in the small bowel was less in those subjects consuming non-aspartame non-sugar sweeteners when compared to controls, whereas bacterial richness in those consuming aspartame was similar to controls,” said Ruchi Mathur, MD, a professor of Medicine at Cedars-Sinai and the lead author of the study.
“Interestingly, when we looked at predicted metabolic pathways in these bacteria, we noted that the pathway of cylindrospermopsin, a toxin, was enriched specifically in small bowel bacteria of subjects who consumed aspartame. This pathway is recognized for its harmful effects on the liver and the nervous system, and it is classed as a potential cancer-causing agent,” said Mathur, an endocrinologist and corresponding author for the paper.
AUTHORS
Other Cedars-Sinai authors include Ava Hosseini, MPH; Gillian M. Barlow, PhD; Gabriela Leite, PhD; Mohamad Rashid, MD; Gonzalo Parodi; Jiajing Wang, PhD; Walter Morales; Stacy Weitsman, MS; Ali Rezaie, MD; and Mark Pimentel, MD.
FUNDING
This research was supported by Frank Lee, the Monica Lester Charitable Trust and the Elias, Genevieve, and Georgianna Atol Charitable Trust.
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