Sucralose is an artificial non-nutritive sweetener used in foods aimed to reduce sugar and energy intake. While thought to be inert, the impact of sucralose on metabolic control has shown to be the opposite. The gut microbiome has emerged as a factor shaping metabolic responses after sweetener consumption. We examined the short-term effect of sucralose consumption on glucose homeostasis and gut microbiome of healthy male volunteers. We performed a randomised, double-blind study in thirty-four subjects divided into two groups, one that was administered sucralose capsules (780 mg/d for 7 d; n 17) and a control group receiving placebo (n 17). Before and after the intervention, glycaemic and insulinaemic responses were assessed with a standard oral glucose load (75 g). Insulin resistance was determined using homeostasis model assessment of insulin resistance and Matsuda indexes. The gut microbiome was evaluated before and after the intervention by 16S rRNA sequencing. During the study, body weight remained constant in both groups. Glycaemic control and insulin resistance were not affected during the 7-d period. At the phylum level, gut microbiome was not modified in any group. We classified subjects according to their change in insulinaemia after the intervention, to compare the microbiome of responders and non-responders. Independent of consuming sucralose or placebo, individuals with a higher insulinaemic response after the intervention had lower Bacteroidetes and higher Firmicutes abundances. In conclusion, consumption of high doses of sucralose for 7 d does not alter glycaemic control, insulin resistance, or gut microbiome in healthy individuals. However, it highlights the need to address individual responses to sucralose.
The current randomised controlled trial found that the consumption of high doses of sucralose for 7 days does not alter glycaemic control or insulin sensitivity in healthy adults. There was also no difference in changes in the gut microbiome composition of the 34 participants following the consumption of sucralose or placebo.
Fasting plasma glucose and fasting serum insulin concentrations were not affected by the daily consumption of sucralose for 1 week, at high doses equivalent to the 75% of the Acceptable Daily Intake for sucralose (15 mg/kg/d). Regarding insulin sensitivity markers, there was no differences between the sucralose and placebo groups. Another important finding of this study is that the microbiome composition was not affected by the interventions, indicating no impact of sucralose consumption on the gut microbiota.
The results of this study are in line with findings of other human trials showing that sucralose consumption does not affect the glycaemic response of healthy individuals (Grotz et al, 2017). This was the first study to examine the impact of a repeated high dose of sucralose on the gut microbiome composition and found no evidence of any effects.