Greater consumption of food prepared outside of the home (OOH) is associated with higher energy intake. Strategies are needed to make eating OOH food less harmful to health. Identifying menu characteristics that contribute to higher energy consumption OOH could aid characterisation of OOH outlets by their relative healthiness and inform future policy intervention in the OOH food sector. Customers (N=3718) were asked to recall their food orders upon exiting a range of OOH outlets across four local authorities in England during 2021 and 2022. For each outlet, universal health rating scores were calculated based on select menu characteristics and deep learning healthiness scores were calculated based on outlet name. Random forest models and robust linear regression models clustered by outlet were used to identify whether outlet healthiness scores and individual menu characteristics were associated with kcal consumed. Universal health rating scores, but not deep learning scores, were predictive of energy consumed during OOH outlet visits (-28.27; 95% CI -44.76 to -11.77; p=.003). Menu characteristics with the greatest importance for predicting energy consumed were the percent of savoury main menu items over 600kcal and 1345kcal, the number of desserts, the number of unique vegetables, and the percent of drinks over 100kcal. Menu characteristics accounted for 29% of variance in energy consumed by customers. Universal health rating scores may be a useful tool to characterise the healthiness of OOH outlets in England. Investigating the potential impact of OOH outlet health ratings on consumer and business behaviour is now warranted.

ER has previously received research funding from Unilever and the American Beverage Association for unrelated research projects. Other authors have no competing interests.

https://osf.io/vx9rb/

Amy Finlay is supported by an ESRC grant (ES/W007932/1). Jean Adams is supported by the Medical Research Council [grant number MC_UU_00006/7]. Yuru Huang is supported by NIHR funding (NIHR130597) and Eric Robinson is funded by the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation programme (Grant reference: PIDS, 803194) and the National Institute for Health and Care Research (NIHR) Oxford Health Biomedical Research Centre (BRC). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care.

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