We investigated the lifestyle factors influencing weight gain in university students during restrictions (mild lockdown) imposed owing to the novel coronavirus disease pandemic in Japan. In this cross-sectional study, a questionnaire survey of Nagasaki University students undergoing health examinations was conducted in 2021. Students reporting >=3 kg weight gain were included in the weight gain group; the remaining students were in the non-weight gain group. Fisher’s exact test and binary logistic regression were performed to detect the associations between weight gain and each lifestyle factor. We included 3,059 respondents (response rate: 45.7%), and 9.5% respondents reported >=;3 kg weight gain. The following factors were associated with weight gain (odds ratio, 95% confidence interval, p value from Fisher’s exact test): dining out for >=4 times/week (2.16 [1.40, 3.32], p = 8.7 × 10−4), gaming time of >=4 h/day (2.26 [1.45, 3.47], p = 2.4 × 10−4). Binary logistic regression among the four highest odds ratios showed that after adjusting for other factors frequently dining out and prolonged gaming time were significantly associated with weight gain. Prolonged gaming and frequently dining out were associated with weight gain in students during the mild lockdown.

The authors have declared no competing interest.

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The present study was conducted with the approval of the ethical review board of Nagasaki University (approval number: 20062604) and in accordance with the principles of the Declaration of Helsinki.

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