Summary: In a randomized crossover trial of 75 young adults across healthy weight, overweight and obesity, acute intake of a sucralose drink raised hypothalamic blood flow versus both sucrose (P<0.018) and water (P<0.019). Greater hunger was seen for sucralose versus sucrose (P<0.001), but no hunger difference was detected versus water.
PICO Summary
| Element | Detail |
|---|---|
| Population | 75 young adults (healthy weight, overweight or with obesity); randomized crossover design; single-site study, United States (ClinicalTrials.gov NCT02945475). |
| Intervention | Acute consumption of a drink containing the non-caloric sweetener sucralose; each participant served as own control (within-subject crossover, n=75). |
| Comparison | Sweetness-matched sucrose drink and water, consumed by the same participants on separate visits (within-subject, n=75). |
| Outcome | Sucralose vs sucrose: increased hypothalamic blood flow (P<0.018) and greater hunger ratings (P<0.001). Sucralose vs water: increased hypothalamic blood flow (P<0.019) but no difference in hunger. Sucrose, but not sucralose, raised peripheral glucose, which was associated with reduced medial hypothalamic blood flow (P<0.007). Sucralose increased functional connectivity between the hypothalamus and motivation and somatosensory regions. No effect sizes, 95% confidence intervals, ARR or NNT were reported in the abstract; outcomes are mechanistic and acute, not measures of food intake or body weight. |
Expert Commentary
This randomized crossover trial is best read as a mechanistic neuroimaging study rather than a verdict on whether sucralose makes people eat more. Acute sucralose was shown to raise hypothalamic blood flow relative to both sucrose and water, and to increase hunger ratings relative to sucrose; the within-subject design and sweetness matching are methodological strengths that reduce confounding. The headline that sucralose drives appetite is only partly supported, since no difference in hunger was detected against water, and the proposed explanation, that sweet taste without post-ingestive glucose fails to suppress the hypothalamus, is plausible but inferred from imaging signals rather than from measured eating. A central limitation is that no food intake or body-weight outcomes were captured, so the clinical meaning of a transient blood-flow change remains uncertain. Can I use this with my patients? Not yet as a reason to abandon non-caloric sweeteners; it is reasonable to reassure a patient swapping sugary drinks for sucralose that this single acute study does not demonstrate weight gain or metabolic harm. The signals warrant longer trials that track actual intake and weight before guidance changes. No commercial sweetener sponsorship was evident, and the modest, biologically plausible effects argue against overinterpretation.
References
Chakravartti SP, Jann K, Veit R, Liu H, Yunker AG, Angelo B, et al. Non-caloric sweetener effects on brain appetite regulation in individuals across varying body weights. Nat Metab. 2025;7(3):574-585. doi:10.1038/s42255-025-01227-8