Sex-specific association of the lunar cycle with sleep

Using one-night sleep recordings from 852 subjects all living in Uppsala, Sweden, the present study represents one of largest polysomnography investigations into association 29.53-day long lunar cycle with among men and women across a wide age range (22–81 years). Following day after new moon until full (also named waxing period), moon's illumination increases, timing meridian is gradually shifted noontime toward midnight. In contrast, waning decreases, early night hours noontime. Thus, we focused on contrast between periods. Sleep duration was shorter nights during period as compared to (P < 0.001). addition, significant interaction effect participants' sex noted 0.05). Men, but not women, exhibited lower efficiency 0.001 P = 0.748, respectively) were longer awake onset 0.010 0.890, period. All associations robust adjustment for confounders (including regular disturbances). Our findings suggest that effects human are more pronounced men. Based cross-sectional design study, no firm conclusions can be drawn causality relations.