{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T14:14:01Z","timestamp":1788444841538,"version":"build-2803163510"},"reference-count":35,"publisher":"BMJ","issue":"6","license":[{"start":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T00:00:00Z","timestamp":1780272000000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"Canadian Institutes of Health Research (CIHR","award":["PJT-178394"],"award-info":[{"award-number":["PJT-178394"]}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,5,6]]},"published-print":{"date-parts":[[2026,6]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To examine the impact of the COVID-19 pandemic on body mass index (BMI) and obesity status among Canadian residents and explore how this association varied by sociodemographic and health status.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>Prospective cohort study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>Canada.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>41\u2009302 adults, aged 45\u201385 at baseline, participating in the Canadian Longitudinal Study on Aging.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Primary and secondary outcomes<\/jats:title>\n                    <jats:p>BMI and BMI-defined obesity were measured at baseline, follow-up 1 and follow-up 2 (FUP2), with 33% of FUP2 data (n=13\u2009444) gathered after 16 March 2020, when COVID-19 restrictions began. Correction factors were applied for self-reported BMI and weighted generalised estimating equations assessed BMI changes before and during the pandemic.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>We found a significant interaction between follow-up time and timing of FUP2 data collection (before or during the pandemic). Participants measured during the pandemic had an excess BMI increase of 0.21\u2009kg\/m\u00b2 (95%\u2009CI 0.15 to 0.28) and 1.06 times higher odds of obesity (95%\u2009CI 1.03 to 1.09) compared with prepandemic trends. Increases were more pronounced among females, middle-aged adults and those without diabetes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The COVID-19 pandemic was associated with a modest increase in BMI and obesity among Canadian adults. Ongoing research is needed to assess long-term trends.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2026-116378","type":"journal-article","created":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T13:10:38Z","timestamp":1780319438000},"page":"e116378","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Impact of the COVID-19 pandemic on obesity: a prospective cohort study of the Canadian Longitudinal Study on Aging (CLSA)"],"prefix":"10.1136","volume":"16","author":[{"given":"Mohammad Nazmus","family":"Sakib","sequence":"first","affiliation":[{"name":"Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2794-9692","authenticated-orcid":false,"given":"Lauren E","family":"Griffith","sequence":"additional","affiliation":[{"name":"Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Urun","family":"Erbas Oz","sequence":"additional","affiliation":[{"name":"Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4951-6353","authenticated-orcid":false,"given":"Nicole E","family":"Basta","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8072-2836","authenticated-orcid":false,"given":"Hertzel C","family":"Gerstein","sequence":"additional","affiliation":[{"name":"Department of Medicine, McMaster University, Hamilton, Ontario, Canada"},{"name":"Population Health Research Institute, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason D","family":"Morgenstern","sequence":"additional","affiliation":[{"name":"Renfrew County and District Health Unit, Pembroke, Massachusetts, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susan","family":"Kirkland","sequence":"additional","affiliation":[{"name":"Department of Communcity Health and Epidemiology, Dalhousie University, Halifax, Nova Scotia, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0355-9734","authenticated-orcid":false,"given":"Lehana","family":"Thabane","sequence":"additional","affiliation":[{"name":"Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada"},{"name":"St Joseph\u2019s Healthcare Hamilton, Hamilton, Ontario, Canada"},{"name":"University of Johannesburg Faculty of Health Sciences, Johannesburg, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2785-1246","authenticated-orcid":false,"given":"Brendan T","family":"Smith","sequence":"additional","affiliation":[{"name":"Public Health Ontario, Toronto, Ontario, Canada"},{"name":"University of Toronto Dalla Lana School of Public Health, Toronto, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cynthia","family":"Balion","sequence":"additional","affiliation":[{"name":"Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacqueline M","family":"McMillan","sequence":"additional","affiliation":[{"name":"Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Parminder","family":"Raina","sequence":"additional","affiliation":[{"name":"Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada"},{"name":"McMaster University McMaster Institute for Research on Aging, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6106-5073","authenticated-orcid":false,"given":"Laura N","family":"Anderson","sequence":"additional","affiliation":[{"name":"Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,6,1]]},"reference":[{"key":"2026090306255414000_16.6.e116378.1","doi-asserted-by":"publisher","DOI":"10.1016\/j.maturitas.2009.09.006"},{"key":"2026090306255414000_16.6.e116378.2","unstructured":"Government of Canada, Statistics Canada . 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