Shift work, sleep duration, and body image dissatisfaction among female workers in southern Brazil

We examined the association between shift work and sleep duration with body image dissatisfaction (BID) among shift-working women in southern Brazil. In this cross-sectional study, data of 505 women shift workers, between 18 and 60 years old, were collected between January and April 2011. BID was assessed using the Stunkard Figure Rating Scale. Information on shift work, sleep duration, and other explanatory variables was collected through a questionnaire. An aggregated exposure variable was created and termed "sleep deprivation," with the exposure category being night-shift workers who slept < 7 h/day. The respective prevalence ratio values were estimated using a Poisson regression. The prevalence of BID among shift-working women was 42.4 (95% CIs = 38.0 to 46.7%), and 199 (93.0%) of these women wished they had a smaller body size. Shift work (PR = 1.40; p = 0.006) and sleep duration (PR = 1.32; p = 0.010) were independently associated with BID. Additionally, workers with sleep deprivation exhibited a higher probability of BID than those without sleep deprivation (PR = 1.31; p = 0.012). These results reveal a situation of vulnerability and the need for strategies and actions directed at shift-working women with the aim of reducing the effects of sleep deprivation on mental health, particularly with regard to body image disorders.