@article{discovery10087074,
         journal = {International Journal of Obesity},
           title = {Long working hours and change in body weight: analysis of individual-participant data from 19 cohort studies},
            year = {2019},
           month = {November},
            note = {This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.},
        abstract = {OBJECTIVE
To examine the relation between long working hours and change in body mass index (BMI).

METHODS
We performed random effects meta-analyses using individual-participant data from 19 cohort studies from Europe, US and Australia (n = 122,078), with a mean of 4.4-year follow-up. Working hours were measured at baseline and categorised as part time ({\ensuremath{<}}35 h/week), standard weekly hours (35-40 h, reference), 41-48 h, 49-54 h and {$\ge$}55 h/week (long working hours). There were four outcomes at follow-up: (1) overweight/obesity (BMI {$\ge$} 25 kg/m2) or (2) overweight (BMI 25-29.9 kg/m2) among participants without overweight/obesity at baseline; (3) obesity (BMI {$\ge$} 30 kg/m2) among participants with overweight at baseline, and (4) weight loss among participants with obesity at baseline.

RESULTS
Of the 61,143 participants without overweight/obesity at baseline, 20.2\% had overweight/obesity at follow-up. Compared with standard weekly working hours, the age-, sex- and socioeconomic status-adjusted relative risk (RR) of overweight/obesity was 0.95 (95\% CI 0.90-1.00) for part-time work, 1.07 (1.02-1.12) for 41-48 weekly working hours, 1.09 (1.03-1.16) for 49-54 h and 1.17 (1.08-1.27) for long working hours (P for trend {\ensuremath{<}}0.0001). The findings were similar after multivariable adjustment and in subgroup analyses. Long working hours were associated with an excess risk of shift from normal weight to overweight rather than from overweight to obesity. Long working hours were not associated with weight loss among participants with obesity.

CONCLUSIONS
This analysis of large individual-participant data suggests a small excess risk of overweight among the healthy-weight people who work long hours.},
             url = {https://doi.org/10.1038/s41366-019-0480-3},
          author = {Virtanen, M and Jokela, M and Lallukka, T and Magnusson Hanson, L and Pentti, J and Nyberg, ST and Alfredsson, L and Batty, GD and Casini, A and Clays, E and DeBacquer, D and Ervasti, J and Fransson, E and Halonen, JI and Head, J and Kittel, F and Knutsson, A and Leineweber, C and Nordin, M and Oksanen, T and Pietil{\"a}inen, O and Rahkonen, O and Salo, P and Singh-Manoux, A and Stenholm, S and Suominen, SB and Theorell, T and Vahtera, J and Westerholm, P and Westerlund, H and Kivim{\"a}ki, M}
}