Quality of sleep matters for your health, not just the duration

The American National Sleep Foundation recommends that adults get seven to nine hours sleep each night. Many people fall short of this because they restrict their sleep to make way for a change in their life, such as having a new baby, taking on a new job that starts much earlier, or moving to a new home that is further from work. Our latest research shows the detrimental effect this can have on some people’s health – some, but not all.

Our study, published in the journal Sleep, shows that adults who restrict their sleep by two or more hours each night are more likely to suffer a respiratory illness, but only in those reporting poor sleep quality. Adults who don’t get the recommended amount of sleep but report getting a good night’s sleep seem to be protected from respiratory illness, including colds, flu and COVID.

Good sleep quality is associated with a stage of sleep known as “slow-wave sleep”.