Abstract
Background/Objectives: Low quality diets are a risk factor for non-communicable diseases; therefore, improving diet quality is a public health and policy priority in the UK and elsewhere. Reformulating food/beverage products to make them healthier may be an effective approach. Evidence suggests that fiscal interventions, notably taxes/levies on soft drinks, can lead to reformulation but the evidence for voluntary or mandated non-fiscal interventions is less clear. We aimed to review and synthesise contemporary evidence to determine whether non-fiscal policies/interventions result in the reformulation of food/beverage products Methods: In April 2023, we systematically searched ten international academic and nine grey literature databases. We included real-world study designs, all nutrients, in- and out-of-home sectors, and studies published from 2013, to ensure policy relevancy. We excluded modelling studies. Using the Synthesis Without Meta-Analysis method we conducted vote counting of studies based on the direction of effect and narrative synthesis by intervention type. Risk of bias was assessed using a tool developed by the EPPI-Centre and quality was assessed using GRADE. Results: We included 77 real-world studies from 19 countries, reporting 100 non-fiscal policies/interventions. Most commonly, these were reduction targets (n = 44), front-of-pack labels (n = 23), and advertising standards (n = 9). Most interventions were voluntary (n = 67), compared to mandatory (n = 33), and focused on the in-home sector (n = 63). The vote counting results showed non-fiscal policies/interventions overall led to improvements in reformulation in 60/63 studies with a valid direction of effect (95%, 95% CI 0.869, 0.984, p < 0.001). Mandatory implementations were more successful than voluntary implementations with 15/15 showing an improvement (100%, 95% CI 0.796, 1], p < 0.001), compared 40/43 showing an improvement (93%, 95% CI 0.814, 0.976, p < 0.001). Most of the studies were of low quality, due to the observational nature of the studies. Sodium was the most commonly targeted nutrient (n = 56) and was found to be reformulated in most studies. Causation is difficult to establish from real-world studies, but evidence suggests that regulatory and multi-component strategies may be effective at driving reformulation. Conclusions: Non-fiscal policies/interventions can play an important role in driving reformulation, alongside fiscal measures. This work was funded by the National Institute for Health and Care Research PRP-PRU-02-15-Healthy Weight and registered on Open Science Framework.