Artificial Sweeteners Linked to Gut Microbiome Shifts and Reduced Glucose Tolerance

A 2022 randomized‑control trial conducted by the Weizmann Institute of Science examined the short‑term effects of four common artificial sweeteners—saccharin, sucralose, aspartame and stevia—on the gut microbiome of 120 healthy adults. Participants consumed daily doses below the admissible daily intake for two weeks.

The study found sweetener‑specific changes. Saccharin and sucralose produced the most pronounced alterations in gut bacterial composition and were associated with a statistically significant decline in glucose tolerance. Aspartame caused measurable microbiome shifts but did not affect glucose regulation, while stevia showed microbiome changes without a significant impact on glucose tolerance. The researchers suggest that saccharin’s slow intestinal absorption and sucralose’s near‑unchanged excretion may underlie their stronger interaction with gut microbes.

These findings raise concerns about the metabolic consequences of widely consumed “zero‑calorie” products such as diet sodas, protein puddings and low‑carb snacks that contain these sweeteners.