When male mice of a common lab breed drank aspartame instead of water for a long time, their blood sugar took longer to go back down after eating, meaning their bodies didn’t handle sugar as well.

When male mice of a common lab breed ate food with artificial sweeteners instead of plain water for a long time, they didn’t gain more or less weight, fat, or muscle, and they ate about the same amount of food as mice that only drank water.

Eating or drinking things with aspartame doesn’t seem to raise or lower blood sugar, insulin, or fat levels in people with diabetes, according to some small studies.