A recent study has found that lack of sleep can make you feel several years older than your actual age. The findings were published on March 27th in the Proceedings of the Royal Society B: Biological Sciences.
An individual's age or "subjective age" is influenced by various physical and mental health conditions, especially depression. "Age is not just a perception," says Leonie Balter from the Karolinska Institute in Sweden. "We know that those who feel younger than their actual age tend to live healthier and longer lives."
Adequate sleep makes you feel younger. Image Source: Uwe Krejci/Getty Images
Given the importance of sleep for our overall well-being, Balter and colleague John Axelsson decided to investigate whether sleep affects people's "subjective age".
Researchers recruited 429 individuals aged 18 to 70 and surveyed their "subjective age" along with their sleep duration over the past 30 days.
They found that insufficient sleep was associated with participants feeling older than their actual age, with each day of inadequate sleep increasing their "subjective age" by an average of 0.23 years. In contrast, those who had sufficient sleep over the past 30 days felt on average 5.81 years younger than their actual age.
In the second part of the study, researchers recruited another 186 participants. Over a two-week period, these participants were asked to maintain 9 hours of sleep for two consecutive nights, recorded through sleep logs and wrist-worn sleep tracking devices. They were then instructed to restrict their sleep to 4 hours or less for two consecutive nights.
Following sleep restriction, participants reported feeling an average increase of 4.44 years older than their actual age, while under the 9-hour sleep condition, they felt on average 0.24 years younger than their actual age. Compared to those feeling least fatigued, individuals feeling most fatigued believed they aged around 10 years.
Balter noted that the study's findings suggest sleep is a key indicator of some people's "subjective age," which correlates with their health. "If you take care of your sleep, you'll feel younger," she said.
Related paper: https://doi.org/10.1098/rspb.2024.0171
