A recent study has said that women are more affected by night shift work than men. The study was conducted by researchers at the University of Surrey in the UK, and was published in the journal PNAS.
16 males and 18 females were part of the study. They were placed on 28 hour days in a controlled environment without light dark cycles. Similar to jet lag or a shift work scenario, this desynchronised the sleep wake cycle from the brains circadian or 24 hour clock.
The researchers said, Every three hours during the awake period, participants performed a wide range of tests, including self-reported assessments of sleepiness, mood and effort, and objective tests of cognitive performance which included measures of attention, motor control and working memory.
Brain electric activity was monitored continuously during sleep. The results showed that in both men and women, self-reported assessments were more sensitive to the effects of time awake and circadian clock than the many objective measures of performance. We show for the first time that challenging the circadian clock affects the performance of men and women differently.
Our research findings are significant in view of shift work-related cognitive deficits and changes in mood. Extrapolation of these results would suggest that women may be more affected by night-shift work than men. These results show that in both men and women circadian rhythmicity affects brain function and that these effects differ between the sexes in a quantitative manner for some measures of brain function.