Sweeteners · Gut & Microbiome
acesulfame-K alters gut microbiome
Part of: • acesulfame-K
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: Population patterns (Observational)
How the studies fall
What the evidence shows
Acesulfame-K's effect on the human gut microbiome is weakly supported — some reviews and animal work suggest it can shift microbiota, but the human clinical trials that changed microbiota implicated saccharin and sucralose, not ace-K. So, like aspartame, the microbiome concern for ace-K specifically is largely mechanistic/animal, not demonstrated in people. measured_by:: [[gut microbiome]]
The evidence (8)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Feng et al. 2024 · Metabolites | observational | mixed | low | NAS-microbiome review: ace-K effects sporadic, human data limited. |
| Khattab 2026 · Curr Nutr Rep | observational | supports | low | Mechanistic review: ace-K among sweeteners that can modulate microbiota (largely preclinical). |
| Al-Ishaq et al. 2023 · Nutrients | observational | mixed | low | Sweeteners-microbiome review: ace-K evidence sparse/inconclusive. |
| Iizuka 2022 · Nutrients | observational | mixed | low | Review: artificial sweeteners incl. ace-K may alter microbiota, evidence mixed. |
| Gauthier et al. 2024 · Nutrition | observational | contradicts | moderate | Human clinical-trial review: only saccharin and sucralose changed microbiota — not ace-K. |
| Del Pozo et al. 2022 · Nutrients | observational | mixed | low | Review focused on sucralose/saccharin: ace-K evidence sparse. |
| Conz et al. 2023 · Nutrients | observational | supports | moderate | NNS–microbiota review: ace-K among sweeteners reported to affect microbiota (largely preclinical). |
| Ruiz-Ojeda et al. 2019 · Adv Nutr | observational | contradicts | moderate | Review: only saccharin, sucralose and stevia measurably change human gut microbiota — implying ace-K does not. |
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