Chronic non-nutritive sweetener and sugar consumption alter decision-making and risk-taking in young healthy adults

Background: Non-nutritive sweeteners (NNS)—such as aspartame, acesulfame-K, sucralose, and saccharin—are increasingly used as sugar substitutes to enhance food palatability without additional caloric intake. While the metabolic effects of NNS are well documented, their potential cognitive and socio-emotional consequences remain unclear. Objective: This study investigated the associations between chronic NNS and sugar consumption, cognitive performance, and socio-emotional behaviors in healthy young adults, while controlling for sugar intake to isolate substance-specific effects.Methods: A total of 291 French adults aged 18-30 years completed five computerized tasks assessing decision-making and emotion regulation: the Iowa Gambling Task (IGT), the Game of Dice Task (GDT), the binary dictator game, the Prisoner’s Dilemma, and the Emotion Regulation Questionnaire (ERQ). Daily NNS and sugar intakes were estimated using quantitative food frequency questionnaires. Logistic mixed-effects regression models were used to examine the effects of NNS and sugar intake on choice probabilities, rigidity scores, and response times.Results: Higher NNS intake was associated with increased selection of the riskiest options under explicit risk in the GDT (p = 0.04) but did not affect decision-making in the IGT. Conversely, higher sugar intake was positively associated with selecting the advantageous yet risky option compared to both disadvantageous (p = 0.04) and advantageous non-risky (p = 0.02) options during the early ambiguity (learning) phase of the IGT. Sugar intake also tended to increase selection of the riskiest option (versus the safest option) under explicit risk. NNS intake was further linked to shorter mean response times across IGT trials (p = 0.04) and showed a trend toward higher rigidity scores at the end of the task, whereas sugar intake predicted longer response times (p < 0.01) and tended to decrease rigidity scores. Neither NNS nor sugar intake significantly influenced altruism, cooperation, or emotion regulation.Conclusion: Chronic NNS and sugar consumption appear to differentially modulate decision-making processes under explicit and experiential risk, without significantly impacting social or emotional behaviors. These findings underscore the need for longitudinal and neuroimaging studies to elucidate the neural mechanisms underlying sweetener-related behavioral modulation.