Researchers say you shouldn't feel guilty about catching up on your Z's.
People who get too little sleep are at a significantly greater risk of dying early compared to those who are well-rested.
The study followed the sleep habits of 43,880 subjects over the course of 13 years.
But when the short sleepers slept in on the weekends, their mortality rate did not differ from that of the consistent seven-hour-a-night-ers.
There's no clear-cut answer yet on why sleeping on weekends makes a difference.
Interestingly, people who slept too much, regularly hitting the hay for eight hours or longer a night, also had a worse mortality rate.
Previous studies have found a U?shaped relationship between mortality and (weekday) sleep duration.
Researchers set out to find out how lack of sleep during the week and weekend might impact on a person's mortality rate. Not in the new study. The take home point is that possibly, long weekend sleep may compensate for short weekday sleep.
Epidemiologist and cardiovascular doctor Franco Cappuccio at the University of Warwick in England, also not a member of the research team, said that the study "looks good" but that the authors missed a trick: "a full explanation of the possibility of daytime napping". The individuals were restricted to 4.67 hours of sleep for each 20-hour time period, which is the equivalent to sleeping around 5.5 hours in a 24-hour day. "Sleeping less than seven hours per night on a regular basis is associated with adverse health outcomes", the academy wrote in a consensus statement.
The Centers for Disease Control and Prevention recommends adults aged 18-60 get at least seven hours of sleep per night. That, Dr Akerstedt said, was perhaps because older individuals got the sleep they needed.