7. Conclusion
This rapid review examined how OOH businesses have responded to menu calorie labelling policies across a range of jurisdictions. The evidence indicates that mandatory schemes are associated with substantially higher levels of compliance than voluntary approaches. In mandatory settings, studies commonly reported high levels of calorie display on in-store menus, for example 80% of outlets displaying calorie information after implementation in England and 94% compliance among the largest US chains after federal implementation, whereas voluntary provision remained low, for example 7% of businesses in Ireland and 17% of large UK chains before implementation in England. Compliance nevertheless remained variable, particularly across digital ordering platforms and in relation to accuracy of information provided. Implementation also involves ongoing operational demands, and enforcement capacity influences consistency of application.
Observed changes in menu calorie content following implementation are generally small and heterogeneous. Where reductions were observed, they were typically in the order of a few kilocalories per menu item or tens of kilocalories per transaction, rather than evidence of large-scale reformulation of existing menus. Reductions are more commonly observed in newly introduced products or in calories purchased per transaction than through systematic reformulation of established menu items. In several contexts, reductions appear to pre-date formal enforcement, suggesting that labelling operates alongside broader market and policy influences rather than as a standalone driver of reformulation.
The current evidence base focuses predominantly on calorie disclosure. There is limited empirical assessment of whether providing broader nutrient information would lead to different reformulation practices, product availability, or consumer purchasing behaviour. Similarly, the resource implications for businesses and enforcement authorities are not consistently quantified.
These findings suggest that menu labelling can improve transparency and achieve high levels of compliance under mandatory regimes but is unlikely on its own to drive large reductions in the energy content of OOH food choices. Further research is needed to examine longer-term effects, broader nutrient impacts, and implementation models that balance effectiveness with feasibility.