But people who managed less than five hours each day for a week, then around six to seven hours at the weekend were no more likely to die than those who consistently slept six to seven hours a day over the same period.
"The assumption in this is that weekend sleep is a catch-up sleep", said Dr Akerstedt, though he noted the study did not prove that to be the case. "Among individuals ≥65 years old, no association between weekend sleep or weekday/weekend sleep durations and mortality was observed". They might sleep six hours or slightly less. Lack of sleep can have dire consequences for your health.
Previous studies have found a U‐shaped relationship between mortality and (weekday) sleep duration. The findings showed that people who slept for short amounts of time during the week and the weekend had a 52% increased rate of mortality.
Curiously, after the age of 65, there is no relationship between sleep duration and mortality. If you don't get enough sleep, you wake up with that sleep pressure and start the day with a higher need for it. People in their late teens and 20s slept on average for seven hours a night during the week but 8.5 hours on days off. "Perhaps it's giving them hope that this habit is in some way good for them".