Free sugar intakes are currently higher than recommended for health, yet effective strategies for reducing consumption are yet to be elucidated. This work investigated the effects of different dietary recommendations for reducing free sugar intakes, on relevant outcomes, in UK adults consuming >5% total energy intake (TEI) from free sugars. Using a randomized controlled parallel-group design, 242 adults received nutrient-based (N=61), nutrient- and food-based (N=60), nutrient-, food- and food-substitution-based (N=63) or no (N=58) recommendations for reducing free sugars at a single timepoint, with effects assessed for the following 12 weeks. Primary outcomes were free sugar intakes as a percentage of TEI (%FS) and adherence to the recommendations at week 12. Secondary outcomes included TEI, diet composition, sugar-sweetened and low-calorie-sweetened food consumption and anthropometry. In Intention-to-Treat analyses adjusted for baseline measures, %FS reduced in intervention groups (%FSchange=-2.5 to -3.3%) compared to control (%FSchange=-1.2%) (smallest B=-0.573, p=0.03), with effects from week 1 until week 12, and no differences between interventions (largest B=0.352, p=0.42). No effects of intervention were found in dietary profiles, but change in %FS was associated with change in %TEI from non-sugar carbohydrate (B=0.141, p<0.01) and from protein (B=-0.171, p=0.02). Body weight was also lower at week 12 in intervention groups compared to control (B=-0.377, p<0.05), but associations with %FS were weak. Our findings demonstrate benefit from dietary recommendations for reducing free sugar intakes in UK adults. Limited advantages were found for the different dietary recommendations, but variety may offer individual choice.

Trial Registration: Clinicaltrials.gov: NCT04816955, registration date: 24.03.21.