biostudies-literatureTaniguchi HHealth and Labour Sciences Research Grants of the Ministry of Health, Labour and Welfare, Japane063213https://www.ebi.ac.uk/biostudies/studies/S-EPMC9716411biostudies-literatureUnknown12(11)<h4>Objectives</h4>The COVID-19 pandemic has had an impact on people's lifestyles such as causing body weight changes. This study examined associations among lifestyle changes and body weight during the COVID-19 pandemic among the Japanese population.<h4>Design</h4>A cross-sectional study.<h4>Setting</h4>A nationwide survey of the general Japanese population.<h4>Participants</h4>Total participants were 2244 men and women, of which 911 young/middle-aged (30-69 years old) and 899 older adults (70 years and older) were analysed separately.<h4>Outcome</h4>Changes in lifestyle (physical activity, dietary habits and alcohol intake) and body weight during the first wave of COVID-19 in spring 2020.<h4>Results</h4>Under the COVID-19 pandemic, 24.1% and 10.1% of Japanese respondents reported weight BMJ openBody weight and lifestyle changes under the COVID-19 pandemic in Japan: a cross-sectional study from NIPPON DATA2010.PMC971641121FA2002Satoh AMiura KKadota AOkuda NArima HNIPPON DATA2010 Research GroupUeshima HHigashiyama ASuzuki HAbe MTaniguchi HOhkubo TOkayama ANishi NfalseBody weight and lifestyle changes under the COVID-19 pandemic in Japan: a cross-sectional study from NIPPON DATA2010.<h4>Objectives</h4>The COVID-19 pandemic has had an impact on people's lifestyles such as causing body weight changes. This study examined associations among lifestyle changes and body weight during the COVID-19 pandemic among the Japanese population.<h4>Design</h4>A cross-sectional study.<h4>Setting</h4>A nationwide survey of the general Japanese population.<h4>Participants</h4>Total participants were 2244 men and women, of which 911 young/middle-aged (30-69 years old) and 899 older adults (70 years and older) were analysed separately.<h4>Outcome</h4>Changes in lifestyle (physical activity, dietary habits and alcohol intake) and body weight during the first wave of COVID-19 in spring 2020.<h4>Results</h4>Under the COVID-19 pandemic, 24.1% and 10.1% of Japanese respondents reported weight 2022-01-01T00:00:00Z2022 Nov2025-04-21T16:12:31.536Z2025-04-21T16:12:31.536ZS-EPMC97164113645042010.1136/bmjopen-2022-063213