Nutritional Impacts of Minimum Unit Pricing for Alcohol: Are there unintended diet consequences?

Background In 2018, Scotland introduced a Minimum Unit Pricing (MUP) policy to remove very-low-cost alcoholic drinks from the market and reduce adverse social and health-related impacts of excessive alcohol consumption. Any increased spending on alcohol may reduce spending on food, and adversely impact diet quality. Objectives To estimate the effect of MUP on dietary energy, nutrients and diet quality. Methods Analyses were conducted on household level purchase data, collected by Kantar Worldpanel (KWP) over 53 weeks before and 54 weeks after the introduction of MUP, from 1987 households in Scotland and 6064 households in the north of England. Energy and food purchases were adjusted to per adult-equivalent values after accounting for estimated unavoidable food waste. Difference-in-differences analyses were conducted for energy, energy density, Diet Quality Index, and foods and nutrients that are relevant to the Scottish dietary goals. The Poisson pseudomaximum likelihood regression model with household fixed-effects was used, with estimates adjusted for age of main shopper, household composition, duration of KWP participation, total spending on non-food items, and month of the year. The effects of area level deprivation and levels of alcohol purchase were also explored. Results The introduction of MUP in Scotland led to a 1.6% (95% Confidence Interval (CI) 0.02% - 3.16%) reduction in sugar purchase or 8 grams per adult-equivalent per week. This reduction was partly a result of a 16.6% (95% CI 7.15% - 25.96%) reduction in sugar from alcoholic drinks purchased. No significant associations were found between MUP and energy, energy density, other nutrients or diet quality. Households from more deprived areas, or with greater alcohol purchases, had greater levels of sugar reduction from alcohol. Conclusions The introduction of MUP in Scotland was associated with small, but beneficial, statistically significant reductions in the purchase of sugar. There was no significant change in overall diet quality. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement The study was funded by a research grant from the Chief Scientist Office (CSO) of the Scottish Government Health and Social Care Directorates, HIPS Grant Number HIPS/19/01. The Health Economics Research Unit is also partly funded by the CSO. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This project used anonymised secondary data (Kantar World Panel) for which informed consent was received by the original data collectors. No further ethical approval was required for this project. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes Kantar Worldpanel data are not publicly available but can be purchased from Kantar Worldpanel (http://www.kantarworldpanel.com). The authors are not legally permitted to share the data used for this study.