Objective:
     
     This study evaluated the effectiveness of health literacy interventions aimed at reducing sugar and sugar-sweetened beverage (SSB) intake among Asian populations and identified the common characteristics of effective interventions through a systematic review of randomised and non-randomised studies.
   

Study design:
     
     Systematic review of randomised and non-randomised trials.
   

Methods:
     
     A systematic search of five databases identified randomised and non-randomised studies on health literacy interventions aimed at reducing sugar and SSB intake among Asian populations. Screening followed predefined criteria, and data extraction captured the intervention type, delivery, duration, and outcomes. Quality was assessed using the Cochrane Risk of Bias-2 and ROBINS-I tools for bias, and the findings were synthesised to identify effective intervention traits and research gaps.
   

Results:
     
     Of the eight included studies, three were face-to-face educational, one behavioural, one online, one mobile text messaging, and two front-of-pack (FOP) labelling interventions. Six out of eight studies measured sugar intake, with four assessing SSB intake. Seven studies reported significant dietary improvements. Overall, bias risk was present, with three rated high. Significant inconsistencies in the two studies were further explored.
   

Conclusion:
     
     The effectiveness of health literacy interventions in reducing sugar or sugar-sweetened beverage intake was positive, particularly for face-to-face interventions and FOP labels. Available evidence may inform policymaking for the implementation of health promotion for disease prevention and complement standards of care practices for disease management.