Background: Several health organizations recommend lowering the consumption of sweet-tasting foods. The rationale behind this recommendation is that a lower exposure to sweet foods may reduce preferences for sweet tasting foods, thus lowering sugar and energy intake, and in turn aiding in obesity prevention. However, empirical data supporting this narrative are lacking. In fact, relatively little is known about the contribution of long-term sweet taste exposure on one’s sweetness preferences. Methods: The primary objective of this randomized controlled trial is to assess the effect of low, regular and high dietary sweetness exposure on preference for sweet foods and beverages, and to compare these effects between intervention groups. One hundred and eighty adults aged 18–65 years with a BMI of 18.5–30.0 kg/m² will be recruited and randomly allocated to either: low dietary sweetness exposure (LSE) (10–15% daily energy from sweet tasting foods), regular dietary sweetness exposure (RSE) (25–30% daily energy from sweet tasting foods), or high dietary sweetness exposure (HSE) (40–45% daily energy from sweet tasting foods), for 6 months, followed by a 4-month follow up. Intervention foods are provided ad libitum, covering approximately 50% of the daily number of food items, to include sugar-sweetened, low-calorie-sweetener-sweetened and non-sweet foods. The primary outcome measure is the difference in change in sweetness preference from baseline to 6 months between intervention groups. Secondary outcomes include: change in sweet taste preferences at different time-points; taste intensity perception; behavioral outcomes: food choice and intake, sweet-liker type, food cravings, dietary taste preferences and dietary taste patterns; anthropometric outcomes: body composition, waist-hip circumference, body weight; and biochemical outcomes: glucose variability and biomarkers related to CVD and diabetes. Discussion: This study will generate important data on the effect of dietary sweetness exposure on sweetness preferences in terms of effect size and change, duration of change and its impact on food intake, body weight status and associated health outcomes. Trial Registration: The study protocol has been registered on ClinicalTrials.gov (ID no. NCT04497974, Registered 4 August 2020, https://clinicaltrials.gov/ct2/show/NCT04497974) and approved by Wageningen’s Medical Ethical Committee (ABR no. NL72134).

Background: Childhood and adolescence represent a critical period for shaping long-term dietary habits, including whole grain consumption, which remains low despite well-documented health benefits. Objective: This cross-sectional study (November–December 2024) examined Slovenian adolescents’ attitudes toward whole-grain foods in the context of organized school meals. Methods: Participants aged 10–12 years and 14–19 years (N = 501; mean age 15.6 ± 2.6) completed an online questionnaire assessing knowledge, self-reported consumption frequency, preferences, motivational factors, and food neophobia using the translated Italian Child Food Neophobia Scale (ICFNS). Based on ICFNS scores, participants were classified as low (≤17), medium (18–24), or high (≥25) in food neophobia. Results: Older adolescents demonstrated better knowledge of whole-grain health benefits; however, greater knowledge was not associated with higher self-reported consumption. Food neophobia was strongly associated with lower consumption frequency and reduced willingness to try whole-grain foods, including whole-grain bread, oatmeal, buckwheat porridge and brown rice. Across all groups, taste was the most consistent motivator for trying whole-grain foods. Older adolescents prioritized health and appearance as key reasons for eating more whole grain foods. Conclusions: Findings suggest that improving taste, increasing exposure, and leveraging institutional settings such as schools, where availability, preparation, and social cues can be managed, may be effective in promoting whole-grain food consumption.

Non-nutritive sweeteners (NNSs) are consumed to reduce intake by providing a sweet taste with little to no energy. Despite regulatory approval and extensive use, uncertainty remains about their long-term role in weight management and health, and about whether exposure to sweet taste itself, independent of energy, influences these outcomes. This narrative review synthesizes evidence from three recent European consortia: SWEET, SWITCH and Sweet Tooth, which together provide complementary data from acute, short- and long-term randomized controlled trials. The studies examined the effects of NNSs and dietary sweet taste exposure on body weight, health-related biomarkers, sweet taste preference, and eating behavior. Across studies, replacing sugars with NNSs appeared to support weight loss maintenance, while NNS consumption and dietary sweet taste exposure showed no adverse changes in body weight, glucoregulatory and endocrine biomarkers, cardiometabolic risk factors, gut microbiota, or liver enzymes. Likewise, neither NNS use nor different dietary sweet taste exposure altered sweet taste liking, appetite sensation, energy intake, or food choice. However, interpretation should consider the characteristics of the included studies, including selected populations, intervention context, outcome heterogeneity, and the fact that several behavioral and biomarker outcomes were secondary or exploratory. Overall, the reviewed evidence suggests that replacing sugar intake with NNSs may support weight management strategies, while differences in habitual dietary sweet taste exposure per se appear largely neutral with respect to health-related biomarkers and sweet taste preferences.