Previous research has linked a single night of bad sleep to lower well-being, but multiple nights of inadequate sleep have only been studied in clinical settings where the amount of nightly sleep was manipulated by researchers. This study was the first to look at the effects of consecutive nights of sleep loss that occurred in everyday life, by using daily dairy data from MIDUS.
More than 1,950 participants provided information about how many hours of sleep they received for eight consecutive nights. They also provided daily reports of how many negative and positive emotions they experienced during the same period (such as feeling angry, sad, or frustrated; as well as cheerful, calm, or enthusiastic). Additionally, they reported the number and severity of physical symptoms they experienced each day, such as headaches, backaches, or stomach upset.
Sleep loss was defined as sleeping less than 6 hours a night, and 42% of the sample experienced at least one such night during the eight-day period. Research has shown that more than 6 hours of sleep a night is necessary to support optimal functioning and health for an average adult.
Study results showed that well-being continually worsened after 2 to 7 consecutive nights of sleeping less than 6 hours. Specifically:
- As the number of consecutive nights of sleep loss increased, negative emotions and physical symptoms continued to increase, while positive emotions decreased.
- Both negative emotions and the severity of physical symptoms tended to be the highest after 3 consecutive nights of sleep loss. The rate of increase was less on days 4 and 5, but began to grow again when people experienced 6 or 7 nights of sleep loss in a row.
- Positive emotions continued to decrease with more nights of sleep loss, but the rate of decrease got smaller each night.
- The number of physical symptoms initially increased by 18%, but the rate of increase also got smaller as the number of consecutive nights with inadequate sleep continued.
These results took into account the effects of the prior day’s well-being, whether it was a weekday or weekend, and other health and demographic variables that may have affected the results.
This study showed that in addition to a single night of sleep loss, consecutive nights of sleep loss may also be problematic to our well-being. This is important because continually degraded well-being, such as lingering negative emotions, have been linked to long-term health problems. Thus this study shows the importance of prioritizing good sleep in our daily lives, and the need for interventions for those who spend night after night struggling to get enough sleep.
Lee, S. (2021). Naturally occurring consecutive sleep loss and day-to-day trajectories of affective and physical well-being. Annals of Behavioral Medicine. Advance online publication. https://doi.org/10.1093/abm/kaab055Read the full article at: http://www.midus.wisc.edu/findings/pdfs/2364.pdf