A Novel 30-Day Intervention to Reduce Free Sugar Consumption

Abstract

Background: Excess free sugar consumption has been associated with a number of negative health outcomes particularly obesity, dental caries, and metabolic syndrome. Despite estimates that free sugar consumption is excess of guidelines, few, if any interventions exist to assist people to reduce their intake. Methods: The current study is a one-group pretest-posttest design, evaluating whether and how a 30-day individual intervention to support 129 people seeking to reduce sugar consumption affected outcomes. The primary aim of the study was to evaluate the effect of the intervention on sugar consumption, with secondary analyses evaluating possible effects on psychological variables (such as anxiety), and objective measures i.e., weight and blood pressure. Exploratory analyses tested for possible moderation, evaluating whether the effects of the intervention were consistent across different groups. Results: There were generally large and strong effects of the intervention across self-reported outcomes i.e, sugar consumption, psychological distress, and general well-being. Results for objective measures were more tenuous. There was an effect found for systolic blood pressure, but not for diastolic blood pressure or weight. Moderation analyses conducted on primary and secondary outcomes produced several important findings. First, income did not moderate the effect of the intervention on any outcome measure. Second, self-efficacy moderated the effect of the intervention for K-6 (distress) and WHO-5 (well-being) variables, but not for sugar consumption or objective measures. Third, sugar addiction (as measured by the Yale Food Addiction Scale) moderated sugar consumption and K-6 scores, but not WHO-5 scores or objective measures. Conclusion: The current thesis developed and tested a novel intervention to help people reduce problematic sugar intake. There were generally large and strong effects for self-reported measures, however, this pattern was not observed in objective measures. Findings from the study suggest that (a) people are willing and able to sign up for a sugar reduction intervention, (b) free sugar consumption may be higher than previously thought, and (c) important psychological and demographic variables may indicate differential impacts on who benefits. Taken together, it warrants further research, ideally a fully powered randomised controlled trial.