Review · Nutrition reviews · 2020Abstract only

Sucralose and aspartame: effects on blood sugar and gut hormones

What it found

Most studies found that sucralose or aspartame did not change blood glucose, insulin, or gut hormone levels.

A few trials found changes, but the results across studies disagree.

What they found

Studies in people

Blood glucose

One study found higher glucose concentrations after sucralose consumption, 3 studies found lower concentrations, and 33 studies found no change.

Insulin sensitivity

Three studies reported decreased insulin sensitivity after sucralose consumption, while 1 trial reported an increase.

Gut hormone GLP-1

Only 4 studies reported increased concentrations of glucagon-like peptide 1.

Overall results

Most studies found no effect of aspartame or sucralose on blood glucose, insulin, or gut hormones. Two trials found aspartame affected glucose, insulin, and glucagon-like peptide 1, and a few trials found sucralose did.

What the authors conclude

“In summary, the evidence from the clinical trials conducted to date is contradictory because of the different protocols used.”
Ahmad SY, Friel JK, Mackay DS, 2020

Also in their conclusions

  • They say the evidence from clinical trials so far is contradictory because of the different protocols used.

How it was done

Non-nutritive sweeteners are used to replace sugary sweeteners, which may help with weight and blood sugar control. But it is not clear whether they affect glucose metabolism or gut hormones.

The authors reviewed clinical trials that looked at how consuming aspartame or sucralose affects glucose metabolism and gut hormones.

What it can’t tell you

  • We summarised it from the abstract only.
  • The trials used different protocols, so it is hard to compare them or draw firm conclusions.
  • The results are mixed, so it is not clear whether sucralose or aspartame have any consistent effect on glucose metabolism or gut hormones.

The paper

Title
Effect of sucralose and aspartame on glucose metabolism and gut hormones
Type
ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
Evidence
Studies in people
Summarised from
Abstract only
Cite
Ahmad SY, Friel JK, Mackay DS (2020). Effect of sucralose and aspartame on glucose metabolism and gut hormones. Nutrition reviews. doi:10.1093/nutrit/nuz099PubMed 32065635DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error