Do artificial sweeteners really suppress your appetite and encourage overeating, or can you curb your sweet cravings without increasing your intake? A new controlled study puts this long-standing debate to the test.
study: Acute and long-term effects of sweeteners and sweet taste enhancers on postprandial appetite, palatability, and free energy intake in humans: The SWEET substudy. Image credit: Josep Suria/Shutterstock.com
new research in nutrients investigated whether sweeteners and sweet taste enhancers (S&SE) influence appetite regulation and tested proposed mechanisms such as activation of sweet taste receptors beyond perceived sweetness.
Metabolism and appetite suppressant effects of sweeteners
Non-caloric sweeteners (NCS) and low-calorie sweeteners (LCS) are food additives that collectively constitute sweeteners and sweetness enhancers (S&SE). NCS provides intense sweetness with negligible energy contribution, whereas LCS provides sweetness with a significantly lower energy density (7.7 kJ/g) than sucrose (16.8 kJ/g). Both sweeteners enhance palatability without the glycemic or calorie load. However, their effects on appetite regulation and energy metabolism are still unclear.
There are conflicting institutional recommendations regarding sweeteners. WHO conditionally recommends against NCS for weight management, citing insufficient evidence of long-term obesity reduction and potential risks of non-communicable diseases. A 2020 expert panel consensus reached the opposite conclusion: no negative effects on weight or blood sugar regulation. This discrepancy is mainly due to differences in the weight of evidence, with the WHO favoring observational data, while the expert panel favors RCTs.
Several mechanisms by which S&SE may impair appetite regulation have been proposed, including activation of sweet taste receptors, disruption of the gut microbiota, and uncoupled radial phase responses. Previous studies have shown that some NCS can reach the blood-brain barrier (BBB), and it has been hypothesized that this may contribute to its effects on the hippocampus. However, supporting evidence mainly comes from animal and in vitro models, and human RCT data are still lacking and largely non-confirmatory.
Assessment of acute appetite response to Ace-K/Cyc across weight management stages
The current sub-study was conducted at the Department of Nutrition, Exercise and Sport at the University of Copenhagen, Denmark, as part of the European Horizon 2020 SWEET project. This study investigated the acute effects of an acesulfame potassium/cyclamate (Ace-K/Cyc) mixture on appetite sensation and energy intake compared to water at baseline, after a 2-month weight loss (WL) period, and after a 4-month weight loss maintenance (WLM) period, and evaluated palatability as a potential confounder.
Participants were between 18 and 60 years old, had a body mass index (BMI) >25.0 kg/m2, and regularly consumed sugar-containing products. However, exclusion criteria included chronic diseases or medications that could affect outcome.
The main study consisted of four clinical investigation dates (CIDs) at months 0, 2, 6, and 12. During the WL period, participants followed the Cambridge Weight Plan’s low-energy diet (LED; 3347–4186 kJ/day) with the aim of achieving ≥5% weight loss. After WL, participants were randomly assigned to follow a healthy diet and consume (S&SE group) or avoid (sugar group) S&SE-containing foods and beverages.
This sub-study recruited 30 participants across three study days aligned to CID 1, 2, and 3. Acute responses were assessed daily after a standardized breakfast followed by Ace-K/Cyc or water intake. Each 6-hour test day was preceded by at least a 10-hour overnight fast, during which participants refrained from exercise, coffee, and smoking. After 15 minutes of bed rest, fasting measurements including weight, appetite, and blood samples were obtained.
Appetite sensation and palatability were measured 10 times per test day using a 100 mm electronic visual analogue scale (eVAS).
S&SE shows no clinically relevant effects on appetite or dietary compensation
Of the 30 participants recruited, 26, 22, and 16 completed the test on day 1 (month 0), day 2 (month 2), and day 3 (month 6), respectively. The attrition was thought to be due to study burden, discomfort in the ventilation hood, and personal reasons. Baseline characteristics were comparable between S&SE and saccharide groups and between completers and dropouts.
Fasting appetite ratings were approximately equivalent between groups, with the exception of decreased hunger in the S&SE group on test day 1, and this isolated finding did not persist over subsequent test days and did not translate into differences in well-being, indicating no sustained fasting appetite effect.
There were no significant interactions, dietary effects, or netAUC differences between satiety and fullness at any time of day or test day, including after taste adjustment. A significant time and meal interaction on hunger was identified across test days, with no three-way interaction.
Post hoc analyzes revealed that the S&SE group reported significantly lower hunger than the sugar group at 130 and 160 minutes after drinking. However, when taste was included as a covariate, these differences were reduced, and netAOC hunger did not differ between groups at any period or across test days.
Standardized breakfast was equally rated by both groups. For the test beverages, the Ace-K/Cyc beverages were consistently rated as poor in taste across all test days and visually unappealing at month 0, reflecting differences in palatability compared to the unsweetened water control.
Importantly, despite the inferior taste ratings of the S&SE drinks, participants did not compensate by eating more. Ad libitum energy intake remained comparable throughout the intervention, suggesting that compensatory feeding is not present in this controlled experimental setting.
conclusion
Compared to water, Ace-K/Cyc consistently reduced the desire to eat sweets during both acute and weight loss and maintenance phases, even after accounting for taste differences, suggesting that its effects go beyond palatability.
Ace-K/Cyc also influenced future consumption, but this effect was partially explained by differences in palatability and showed some variability across time points and analyses, suggesting a mixed context-dependent pattern.
Importantly, ad libitum energy intake was comparable to water, indicating that it does not negatively impact energy balance. However, this study was not powered for appetite-related outcomes, and the paper’s sample size calculations suggest that a significantly larger cohort would be needed to detect differences in these endpoints with adequate statistical power. therefore, These findings should be interpreted with caution. In the future, large-scale trials are needed to validate these findings.
Click here to download your PDF copy.
Reference magazines:
-
H. Andersen, S.S., Kjolbek, L., G. Halford, J.C., Harold, J.A., and Leben, A. (2026). Acute and long-term effects of sweeteners and sweet taste enhancers on postprandial appetite, palatability, and free energy intake in humans: The SWEET substudy. nutrients. 18(6). Doi: https://doi.org/10.3390/nu18060948. https://www.mdpi.com/2072-6643/18/6/948
