Background: Most non-caloric artificial sweeteners (NAS) are not digested, but come in contact with the gut microbiota, an interaction that has been associated with impaired glucose control. We aimed to further investigate whether NAS affect insulin sensitivity.

Methods: The study was an open label study where participants acted as their own controls before and after exposure of 240 mg saccharin/day for three months. Participants were 55-65 years old, with a body mass index of 26-29 kg/m2 without diabetes. Insulin sensitivity was assessed by use of hyperinsulinemic-euglycemic clamps and ’M value’ was calculated by dividing the glucose infusion rate during the last 60 minutes of the clamp by body weight (mg/kg/min).

Results: Of the 14 included participants, one did not complete the study. There was no change in insulin resistance after exposure to saccharin. The mean M value difference (∆M) for all participants was 0.0 (SD 1.6). ∆M was not related to age (p value 0.162) or sex (p value 0.578). Individual M values from the first and second insulin clamp are shown in the Figure and indicate some individual responses.

Conclusions: In contrast to the larger epidemiologic studies, we did not observe a strong effect of NAS on insulin sensitivity. Some individuals exhibited impaired insulin sensitivity and we are currently investigating whether individualized responses are dependent on shifts in the gut microbiota.


K. Radholm: None. K. Kalin: None. M. Wennberg: None. M. Woodward: None. F. Bäckhed: Board Member; Self; Metabogen AB. Stock/Shareholder; Self; Metabogen AB. Advisory Panel; Self; Ferring Pharmaceuticals. O. Rolandsson: None.

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