Study details

For the study, researchers used data from the UK Biobank study, a longitudinal study involving 500,000 participants, and biological aging clocks, which use biomedical data and machine learning to determine the physiological age of each organ in the body.

"The hypothesis is that different organs, even within the same person, age at different rates," said Junhao Wen, an assistant professor of radiology at Columbia University and lead author of the study.

Combining the biological aging clocks with participants' self-reported sleep duration, the researchers examined whether aging was linked to the amount of sleep a person was getting.

Overall, the researchers found that for virtually every organ in the body, getting too little or too much sleep was associated with accelerated aging. They found that the "sweet spot" for sleep was between 6.4 and 7.8 hours per night, with the participants who hit that range having better functioning of the immune system, brain and heart, and other organs.

The effects of sleep formed a U-shaped curve, which means small deviations from the ideal sleep range showed smaller amounts of organ aging, while larger deviations showed more substantial aging.

The researchers also found that women needed a bit more sleep than men. In one of the brain clocks the researchers looked at, men seemed to do best with 7.7 hours of sleep on average while women's brains aged the least with 7.82 hours of sleep. They suggested this could be because of hormones or other physiological factors, as well as social factors.

As for why getting too much sleep can lead to accelerated aging, the researchers said poor health could be leading to people sleeping longer. In addition, Wen noted that in some cases, such as depression, sleeping longer could exacerbate the condition.

"When sleep is consistently too short or too long, those processes get disrupted," she added. "Over time, that disruption accumulates at the cellular level."

Tunc Tiryaki, founder of the London Regenerative Institute Clinics, said that the study's findings reinforce "the idea that sleep is one of the most important modifiable lifestyle factors for long-term health."

"We often focus on supplements and advanced biohacking technologies, but sleep remains foundational for recovery, mitochondrial function and cellular repair," Tiryaki said.

Since sleep needs are individual, experts recommend that if you feel tired during the day, you might need to adjust your bedtime a bit earlier and change your habits during the day to support better sleep.

"Have some light exposure if possible within that first 15 to 20 minutes of waking up," said Ana Krieger, a professor of medicine and medical director of the Center for Sleep Medicine at Weill Cornell. "That's very important because it helps regulate the circadian rhythm."

Ultimately, the researchers said the results of this study emphasize the importance of getting quality sleep for the functioning of every part of the body.

"There is nothing that I can do for a patient that's better than a good night's sleep," Lachs said.