{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T00:10:13Z","timestamp":1773879013232,"version":"3.50.1"},"reference-count":32,"publisher":"Public Library of Science (PLoS)","issue":"3","license":[{"start":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T00:00:00Z","timestamp":1773792000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014013","name":"UK Research and Innovation","doi-asserted-by":"publisher","award":["MR\/T043520\/1"],"award-info":[{"award-number":["MR\/T043520\/1"]}],"id":[{"id":"10.13039\/100014013","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000269","name":"Economic and Social Research Council","doi-asserted-by":"publisher","award":["ES\/Y010973\/1"],"award-info":[{"award-number":["ES\/Y010973\/1"]}],"id":[{"id":"10.13039\/501100000269","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000272","name":"National Institute for Health and Care Research","doi-asserted-by":"publisher","award":["302271"],"award-info":[{"award-number":["302271"]}],"id":[{"id":"10.13039\/501100000272","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosdigitalhealth.org"],"crossmark-restriction":false},"short-container-title":["PLOS Digit Health"],"abstract":"<jats:p>While laxatives are designed to manage the symptoms of constipation, they are also known to be misused for weight management, particularly by individuals with eating disorders. This study investigates the relationship between laxative purchases and weight management by examining seasonal trends. Using real-world loyalty card data from a major UK pharmacy retailer spanning December 2013 to December 2014, we analyse self-medication purchasing patterns from 748,375 buyers to explore potential links with weight management behaviours. In pre-registered analysis, we use regression models to investigate our hypotheses: (1) the number of doses purchased would be greater in January compared to the December prior, reflecting motivations in relation to \u201cNew Year\u2019s resolutions\u201d around weight loss, and (2) doses purchased would be greater in May-August compared to the subsequent September, reflecting an increased focus on body image during the summer. We examine differences between stimulant and non-stimulant laxatives, as stimulants are more commonly misused for weight control due to their rapid effects. To validate our findings, we compare purchasing patterns with those for weight management products over the same periods, and also include negative controls of unrelated products, including painkillers, cold and flu, hay fever, and shampoo. Our findings reveal seasonal variations in laxative purchasing, particularly for non-stimulant medications. Purchases increase in January compared to December and are higher in some summer months compared to September, which may be consistent with seasonal patterns in weight-related behaviours. Non-stimulants exhibit greater seasonal fluctuation than stimulants. Purchases of weight management products follow similar patterns, aligning with established seasonal trends in weight loss behaviours. While laxative purchase trends align with those of weight management products, these patterns provide only indirect evidence and cannot confirm underlying intent, like body image concerns. This work highlights an opportunity for loyalty card data to evaluate impacts of policy regulations in a real-world setting.<\/jats:p>","DOI":"10.1371\/journal.pdig.0000963","type":"journal-article","created":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T17:35:44Z","timestamp":1773855344000},"page":"e0000963","update-policy":"https:\/\/doi.org\/10.1371\/journal.pdig.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Using supermarket loyalty card data to investigate seasonal variation in laxative purchases in the UK"],"prefix":"10.1371","volume":"5","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9539-4759","authenticated-orcid":true,"given":"Romana","family":"Burgess","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neo","family":"Poon","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Edward","family":"Sloan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"James","family":"Goulding","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Helen","family":"Bould","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anya","family":"Skatova","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2026,3,18]]},"reference":[{"issue":"1","key":"pdig.0000963.ref001","doi-asserted-by":"crossref","first-page":"143","DOI":"10.3390\/jcm10010143","article-title":"Laxative Use in the Community: A Literature Review","volume":"10","author":"BL Werth","year":"2021","journal-title":"J Clin Med"},{"key":"pdig.0000963.ref002","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1016\/j.jpsychires.2024.12.043","article-title":"Examining the associations between laxative use, substance use, depressive symptoms, and obsessions and compulsions in adults with an eating disorder","volume":"182","author":"BA MacNeil","year":"2025","journal-title":"J Psychiatr Res"},{"issue":"5","key":"pdig.0000963.ref003","doi-asserted-by":"crossref","first-page":"404","DOI":"10.1002\/eat.20267","article-title":"Misuse of laxatives among adult outpatients with eating disorders: prevalence and profiles","volume":"39","author":"R Bryant-Waugh","year":"2006","journal-title":"Int J Eat Disord"},{"issue":"9","key":"pdig.0000963.ref004","doi-asserted-by":"crossref","first-page":"1114","DOI":"10.1002\/eat.22745","article-title":"Is laxative misuse associated with binge eating? Examination of laxative misuse among individuals seeking treatment for eating disorders","volume":"50","author":"R Elran-Barak","year":"2017","journal-title":"Int J Eat Disord"},{"issue":"1","key":"pdig.0000963.ref005","doi-asserted-by":"crossref","first-page":"109","DOI":"10.2105\/AJPH.2019.305390","article-title":"Diet pill and laxative use for weight control and subsequent incident eating disorder in US young women: 2001-2016","volume":"110","author":"JA Levinson","year":"2020","journal-title":"Am J Public Health"},{"issue":"7","key":"pdig.0000963.ref006","doi-asserted-by":"crossref","first-page":"1289","DOI":"10.1002\/eat.23531","article-title":"Diet pill and laxative use for weight control predicts first-time receipt of an eating disorder diagnosis within the next 5\u2009years among female adolescents and young adults","volume":"54","author":"VM Hazzard","year":"2021","journal-title":"Int J Eat Disord"},{"key":"pdig.0000963.ref007","article-title":"Misuse and abuse of over the counter medication: A growing public health concern","author":"K Patil","year":"2025","journal-title":"Int J Sci Res Technol"},{"key":"pdig.0000963.ref008","author":"GOV.UK"},{"issue":"12","key":"pdig.0000963.ref009","doi-asserted-by":"crossref","first-page":"1487","DOI":"10.2165\/11898640-000000000-00000","article-title":"Laxative abuse: epidemiology, diagnosis and management","volume":"70","author":"JL Roerig","year":"2010","journal-title":"Drugs"},{"key":"pdig.0000963.ref010","first-page":"224","article-title":"The self-report method.","volume-title":"Handbook of research methods in personality psychology","author":"DL Paulhus","year":"2007"},{"key":"pdig.0000963.ref011","doi-asserted-by":"crossref","first-page":"105848","DOI":"10.1016\/j.puhe.2025.105848","article-title":"Exploring the use of supermarket loyalty card data in health research: A scoping review","volume":"247","author":"R Burgess","year":"2025","journal-title":"Public Health"},{"issue":"1","key":"pdig.0000963.ref012","doi-asserted-by":"crossref","first-page":"7258","DOI":"10.1038\/s41467-023-42776-4","article-title":"Assessing the value of integrating national longitudinal shopping data into respiratory disease forecasting models","volume":"14","author":"E Dolan","year":"2023","journal-title":"Nat Commun"},{"issue":"11","key":"pdig.0000963.ref013","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0207523","article-title":"Using machine learning to investigate self-medication purchasing in England via high street retailer loyalty card data","volume":"13","author":"A Davies","year":"2018","journal-title":"PLoS One"},{"key":"pdig.0000963.ref014","doi-asserted-by":"crossref","DOI":"10.2196\/41762","article-title":"Association Between Purchase of Over-the-Counter Medications and Ovarian Cancer Diagnosis in the Cancer Loyalty Card Study (CLOCS): Observational Case-Control Study","volume":"9","author":"HR Brewer","year":"2023","journal-title":"JMIR Public Health Surveill"},{"issue":"20","key":"pdig.0000963.ref015","doi-asserted-by":"crossref","DOI":"10.1097\/MD.0000000000010631","article-title":"Chronic constipation: A review of literature","volume":"97","author":"M Forootan","year":"2018","journal-title":"Medicine (Baltimore)"},{"issue":"4","key":"pdig.0000963.ref016","doi-asserted-by":"crossref","first-page":"519","DOI":"10.1038\/sj.ejcn.1602346","article-title":"Seasonal variation in food intake, physical activity, and body weight in a predominantly overweight population","volume":"60","author":"Y Ma","year":"2006","journal-title":"Eur J Clin Nutr"},{"key":"pdig.0000963.ref017","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1016\/j.bodyim.2021.03.004","article-title":"Beach body ready? Shredding for summer? A first look at \u201cseasonal body image\u201d","volume":"37","author":"S Griffiths","year":"2021","journal-title":"Body Image"},{"issue":"1","key":"pdig.0000963.ref018","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1056\/NEJM199801013380109","article-title":"Losing weight \u2014 an ill-fated new year\u2019s resolution","volume":"338","author":"JP Kassirer","year":"1998","journal-title":"N Engl J Med"},{"issue":"2","key":"pdig.0000963.ref019","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1111\/1477-9552.12462","article-title":"Using supermarket loyalty card data to measure the differential impact of the UK soft drink sugar tax on buyer behaviour","volume":"73","author":"A Fearne","year":"2021","journal-title":"J Agric Econ"},{"key":"pdig.0000963.ref020","doi-asserted-by":"crossref","first-page":"113799","DOI":"10.1016\/j.socscimed.2021.113799","article-title":"How do consumers respond to \u201csin taxes\u201d? New evidence from a tax on sugary drinks","volume":"274","author":"E Fichera","year":"2021","journal-title":"Soc Sci Med"},{"key":"pdig.0000963.ref021","doi-asserted-by":"crossref","first-page":"341","DOI":"10.1007\/s10754-018-9257-9","article-title":"Consumption of salt rich products: impact of the UK reduced salt campaign","volume":"19","author":"A Sharma","year":"2019","journal-title":"Int J Health Econ Manag"},{"issue":"6","key":"pdig.0000963.ref022","first-page":"589","article-title":"Changes in alcohol purchases from grocery stores after authorising the sale of stronger beverages: The case of the Finnish alcohol legislation reform in 2018","volume":"39","author":"L Uusitalo","year":"2022","journal-title":"Nordisk Alkohol Nark"},{"key":"pdig.0000963.ref023","author":"GOV.UK"},{"key":"pdig.0000963.ref024","doi-asserted-by":"crossref","first-page":"100136","DOI":"10.1016\/j.hpopen.2025.100136","article-title":"The regulation on the use of supplements for weight control: Case studies from Australia, the United States of America, and the United Kingdom","volume":"8","author":"SW Dawson","year":"2025","journal-title":"Health Policy Open"},{"issue":"1","key":"pdig.0000963.ref025","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s41746-024-01231-4","article-title":"Overcoming biases of individual level shopping history data in health research","volume":"7","author":"A Skatova","year":"2024","journal-title":"npj Digit Med"},{"key":"pdig.0000963.ref026","doi-asserted-by":"crossref","DOI":"10.2196\/44599","article-title":"Tensorial Principal Component Analysis in Detecting Temporal Trajectories of Purchase Patterns in Loyalty Card Data: Retrospective Cohort Study","volume":"25","author":"R Autio","year":"2023","journal-title":"J Med Internet Res"},{"issue":"12","key":"pdig.0000963.ref027","doi-asserted-by":"crossref","first-page":"2663","DOI":"10.1017\/S1368980023001842","article-title":"Supermarket Transaction Records In Dietary Evaluation: the STRIDE study: validation against self-reported dietary intake","volume":"26","author":"V Jenneson","year":"2023","journal-title":"Public Health Nutr"},{"key":"pdig.0000963.ref028","article-title":"A slow road from meat dominance to more sustainable diets: An analysis of purchase preferences ((Erkkola, Kinnunen, Vepsalainen, Meinila, Uusitalo, Fogelholm) Department of Food and Nutrition, University of Helsinki, Helsinki, Finland). Located at: Embase Preprint; 2015874370","author":"M Erkkola","year":"2021","journal-title":"medRxiv"},{"issue":"5","key":"pdig.0000963.ref029","doi-asserted-by":"crossref","first-page":"1346","DOI":"10.1016\/j.ajcnut.2024.03.003","article-title":"The dynamics in food selection stemming from price awareness and perceived income adequacy: a cross-sectional study using 1-year loyalty card data","volume":"119","author":"M Fogelholm","year":"2024","journal-title":"Am J Clin Nutr"},{"key":"pdig.0000963.ref030","doi-asserted-by":"crossref","first-page":"108145","DOI":"10.1016\/j.drugalcdep.2020.108145","article-title":"Grocery purchase data in the study of alcohol use - A validity study","volume":"214","author":"T Lintonen","year":"2020","journal-title":"Drug Alcohol Depend"},{"key":"pdig.0000963.ref031","first-page":"4530","article-title":"Who consumes anthocyanins and anthocyanidins? Mining national retail data to reveal the influence of socioeconomic deprivation and seasonality on polyphenol dietary intake","author":"J Harvey","year":"2023","journal-title":"Located at: Scopus"},{"key":"pdig.0000963.ref032","author":"N Poon","year":"2023"}],"container-title":["PLOS Digital Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pdig.0000963","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T17:35:54Z","timestamp":1773855354000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pdig.0000963"}},"subtitle":[],"editor":[{"given":"Tianzhen","family":"Chen","sequence":"first","affiliation":[],"role":[{"role":"editor","vocabulary":"crossref"}]}],"short-title":[],"issued":{"date-parts":[[2026,3,18]]},"references-count":32,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2026,3,18]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pdig.0000963","relation":{},"ISSN":["2767-3170"],"issn-type":[{"value":"2767-3170","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,18]]}}}