A study published in Food Quality and Safety on May 20, 2026, reveals that hunger enhances the appeal of sweet taste independently of caloric content, and that habitual consumers of non-nutritive sweeteners exhibit heightened activity in a brain region associated with self-control. The research, conducted by scientists from Jiangnan University in China and the University of Oxford in the United Kingdom, has implications for understanding sugar consumption and designing effective sugar-reduction strategies.
Excessive sugar intake is a major contributor to obesity, type 2 diabetes, and cardiovascular disease. Non-nutritive sweeteners (NNS) have been widely adopted as low-calorie alternatives, but concerns exist that chronic NNS use might decouple sweet taste from metabolic energy signaling, potentially reshaping taste preferences. Long-term trials have yielded conflicting results, prompting a deeper investigation into how metabolic state and habitual NNS use jointly influence sweet preference.
The study directly compared habitual sugar consumers and habitual NNS consumers. Participants rated sweetness-matched solutions under hungry and satiated conditions. Using subjective ratings, emotional assessments, electrocardiogram (ECG), and functional near-infrared spectroscopy (fNIRS), the team found that participants consistently rated all sweet solutions as more enjoyable when hungry, regardless of whether they contained sugar or NNS. This hunger-driven boost was accompanied by physiological signs of sympathetic arousal, including shortened R-R intervals and increased heart rate. Contrary to expectations, hunger did not selectively favor caloric sugar over non-caloric sweetness.
More notably, habitual NNS consumers showed a distinct neural signature. While their self-reported liking and emotional responses did not differ from sugar consumers, fNIRS revealed significantly stronger oxygenated hemoglobin responses in the left dorsolateral prefrontal cortex (DLPFC), a key region for cognitive control and dietary self-regulation. This neural difference emerged even though samples were tasted blindly and matched for sweetness intensity. The study's emotion analysis involved a small sample of 15 participants per group, so those findings should be interpreted cautiously.
“Hunger seems to turn up the volume on sweetness itself, making it more appealing whether it comes with calories or not,” the authors said. “We also saw that habitual non-nutritive sweetener users showed a stronger brain response in a region linked to self-control. It is as if their brains are working a little harder to keep their sweet intake in check.”
The findings suggest that long-term NNS use may be associated with enhanced prefrontal surveillance during sweet taste processing, potentially reflecting a learned cognitive strategy. The study offers practical guidance: because hunger enhances the appeal of any sweet taste, replacing sugar with NNS in snacks between meals might still satisfy cravings without adding calories. The heightened brain activity in habitual NNS users raises the possibility that these sweeteners could help reinforce cognitive control over food choices, though this remains to be tested.
The research was funded by the National Key Research and Development Program of China and the Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province. The full study is available at https://doi.org/10.1093/fqsafe/fyag046.
