Study Finds Low- and No-Calorie Sweetened Beverages Produce Similar Appetite and Metabolic Responses as Water
Study Summary: Low- and No-Calorie Sweeteners Show Similar Responses to Water in Healthy Adults
One of the largest studies ever examined how flavored waters sweetened with sucrose (sugar) or several low- and no-calorie sweeteners affect the brain, blood sugar, insulin levels, digestion, and appetite in healthy young adults. Researchers used advanced MRI techniques to evaluate brain activity after participants consumed the beverages.
Overall, the study found that flavored waters sweetened with low- and no-calorie sweeteners (sucralose, stevia, monk fruit, and allulose + stevia) produced responses that were largely similar to water. Unlike sucrose (sugar), low- and no-calorie sweeteners did not increase blood glucose or insulin levels. While some sweeteners, particularly stevia and allulose combined with stevia, produced modest differences in activity in certain brain regions involved in reward, these changes did not translate into differences in self-reported ratings in appetite or hunger. The researchers concluded that low- and no-calorie sweeteners generally did not differ from water in their effects on appetite or acute metabolic responses, although some sweeteners may have unique physiological effects that warrant further study.
Key Takeaways:
- Low- and no-calorie sweetened beverages did not raise blood sugar or insulin levels. Only the sugar-sweetened beverages increased glucose and insulin concentrations.
- Most low- and no-calorie sweetened drinks affected the body much like plain water. Researchers found that these beverages generally did not change brain activity related to eating, digestion, or blood sugar compared with water.
- Sweeteners did not increase hunger, or appetite, or blood sugar differently than water. Participants reported similar levels of hunger and desire to eat regardless of which low- and no-calorie sweetener they consumed.
- Some sweeteners showed small effects in brain regions involved in food reward and appetite. However, these differences did not lead to meaningful changes in self-reported ratings of appetite or eating behavior in this study. Stevia and an allulose-stevia blend showed modest activity differences in these areas, while the allulose-stevia blend also slowed digestion in a way similar to sugar. These findings may be related to GLP-1, a hormone that helps regulate digestion and blood sugar, though it is not yet known whether these changes have any real-world impact on eating behavior or health.
Related Resources:
Read the study.
Learn more about sweeteners.