Long-term metabolic effects of non-nutritive sweeteners

Objective

Excessive consumption of added sugars has been linked to the rise in obesity and associated metabolic abnormalities. Non-nutritive sweeteners (NNSs) offer a potential solution to reduce sugar intake, yet their metabolic safety remains debated. This study aimed to systematically assess the long-term metabolic effects of commonly used NNSs under both normal and obesogenic conditions.

Methods

To ensure consistent sweetness level and controlling for the acceptable daily intake (ADI), eight weeks old C57BL/6 male mice were administered with acesulfame K (ace K, 535.25 mg/L), aspartame (411.75 mg/L), sucralose (179.5 mg/L), saccharin (80 mg/L), or steviol glycoside (Reb M, 536.25 mg/L) in the drinking water, on the background of either regular or high-fat diets (in high fat diet 60% of calories from fat). Water or fructose-sweetened water (82.3.gr/L), were used as controls. Anthropometric and metabolic parameters, as well as microbiome composition, were analyzed following 20-weeks of exposure.

Results

Under a regular chow diet, chronic NNS consumption did not significantly affect body weight, fat mass, or glucose metabolism as compared to water consumption, with aspartame demonstrating decreased glucose tolerance. In diet-induced obesity, NNS exposure did not increase body weight or alter food intake. Exposure to sucralose and Reb M led to improved insulin sensitivity and decreased weight gain. Reb M specifically was associated with increased prevalence of colonic Lachnospiracea bacteria.

Conclusions

Long-term consumption of commonly used NNSs does not induce adverse metabolic effects, with Reb M demonstrating a mild improvement in metabolic abnormalities. These findings provide valuable insights into the metabolic impact of different NNSs, aiding in the development of strategies to combat obesity and related metabolic disorders.