The relationship between shift work and body mass index among Canadian nurses

The aim of this study was to examine the relationship between shift schedule and body mass index (BMI) among a sample of Canadian Nurses.

Higher BMI values have been reported for employees working non-standard shifts compared to those working a regular daytime schedule. Little is known about the pathways through which shift work is associated with higher BMI.

This study was a secondary analysis of a sample from National Survey on the Work and Health of Nurses (N=9291).

We found a small, but statistically significant, difference in BMI scores across shift schedule categories with higher BMI scores reported among female nurses working night or mixed shift schedules, compared with those working a regular daytime schedule. Adjustment for working conditions and employer supported facilities did not attenuate the association between shift work and BMI scores.

The potential public health importance of this relationship requires further investigation given the small, but statistically significant, differences observed in this sample.