In a recent study published in The Lancet Public Health, researchers modeled the impact of calorie labeling in out-of-home food businesses on adult obesity prevalence and cardiovascular disease mortality in England.
Population-level diet policies reduce the burden of non-communicable diseases and obesity. The United Kingdom (UK) implemented a mandatory energy labeling policy for out-of-home food businesses in England in April 2022. This required businesses to label energy or calorie information for items on online or in-store menus, third-party apps, food-delivery platforms, and at each point where customers choose their food and drink.
This policy may alleviate the prevalence of obesity and cardiovascular mortality, given that out-of-home businesses are likely to serve high-energy meals associated with increased body mass index (BMI). Energy labeling may allow consumers to make better and healthier food choices. However, there is limited evidence about the long-term effect of menu energy labeling policy on obesity and other related outcomes.
Study: Effect of calorie labelling in the out-of-home food sector on adult obesity prevalence, cardiovascular mortality, and social inequalities in England: a modelling study. Image Credit: ELUTAS / Shutterstock
About the study
In the present study, researchers modeled the impact of menu calorie labeling policy in out-of-home businesses on adult obesity and cardiovascular disease mortality in England. A comparative risk assessment model was built to quantify the (long-term) policy effects over two decades (2022-41). The team modeled the current and full implementation scenarios, which reflect policy deployment to large and all out-of-home businesses, respectively.
Each scenario was compared to baseline, viz., no intervention. The researchers assumed the policy implementation would decrease energy intake by 47 kcal for each meal and that the effect of labeling on consumer behavior would remain consistent over time. Moreover, they assumed that other meals would compensate for a part of the energy intake reduction. Specifically, they assumed, on average, 26.5% energy compensation.
The team conservatively assumed that retailers reduced 15 kcal per meal following policy implementation. Model uncertainty was estimated using the Monte Carlo approach. Labeling was hypothesized to decrease body weight through energy intake reduction, which, in turn, was speculated to impact the cardiovascular mortality risk. The team estimated the change in energy intake and converted it into changes in body weight and, thereby, changes in BMI.
Thus, changes in BMI alter the cardiovascular mortality risk. These data were consequently used to quantify new mortality rates and the number of projected deaths. The model yielded changes in obesity prevalence and the number of deaths postponed or prevented. Finally, the team assessed the equity impact of the policy intervention as the ratio of the most and least deprived groups.
Findings
The existing policy implementation in England was estimated to decrease obesity prevalence by 0.27 percentage points over the next two decades, considering consumer response alone. Obesity prevalence was further reduced by 0.07 percentage points when reformulation of foods was additionally considered. Cumulatively, the current scenario would have led to a 0.31 percentage point lower obesity prevalence.
In contrast, the full implementation scenario would decrease the prevalence of obesity by 2.65 percentage points, considering consumer response and reformulation. Without any policy, there would have been around 830,000 cardiovascular disease deaths by 2041. The current scenario would have postponed or prevented 730 cardiovascular disease deaths over two decades, considering consumer response and reformulation.
Notably, the full implementation scenario would have prevented or postponed 9,200 cardiovascular disease deaths. Ratios of obesity prevalence or cardiovascular mortality between the most and least deprived quintile groups were constant. This meant that the policy did not widen health inequalities in obesity or cardiovascular mortality, assuming that the policy effect would be the same across the socioeconomic spectrum.
Conclusions
The study modeled the likely effects of the calorie labeling policy in England. It revealed that the current implementation scenario would reduce the prevalence of obesity by 0.31 percentage points and prevent or postpone 730 deaths over two decades. There was no evidence that the existing implementation would widen existing health inequalities, under the assumption that the effect of the policy was the same across ages, sexes, and socioeconomic positions. However, the benefits would markedly increase if the policy were implemented across all out-of-home food businesses, emphasizing that the full implementation scenario would maximize the effect.
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