A new study published in PLOS Medicine — a peer-reviewed weekly medical journal — on Tuesday reveals older individuals obtaining inadequate sleep have an increased risk of developing numerous chronic diseases.
The massive study from the United Kingdom, funded in part by the U.S. National Institute on Aging, analyzed almost 8,000 civil servants with no chronic disease at the age of 50.
Participants reported sleep levels every four to five years throughout the quarter-century study.
Researchers found that participants who slept five hours or less each night increased their risk of chronic disease by 30% compared to peers getting a minimum of seven hours of nightly rest.
The risk factor increased as the participant aged — 32% at age 60, growing to a 40% greater risk at age 70.
The list of diseases impacted by not getting enough sleep is long, including diabetes, cancer, stroke, depression, and dementia.
While other studies have similarly uncovered the health threats linked with insufficient sleep, they also found risks associated with sleeping too long — something the new report did not touch on.
While the new study’s findings help shed light on the importance of sleep, there are some caveats. By and large, the subjects were predominantly white males from a healthier demographic than the general population.
Additional research may be needed to help draw conclusions outside of this demographic.
Further, the participants had to self-report sleep duration, which is a less reliable method of tracking compared with direct observation by researchers.
According to the study, “The present findings along with evidence from previous studies show the importance of sleep duration across the life course for health outcomes at older ages.”
The director of the prelicensure nursing program and associate professor at the Mervyn M. Dymally School of Nursing, Sharon Cobb, told CNN that the latest findings provide new evidence that poor sleep maps closely to chronic disease.
“I think for a long time, we’ve stressed that you need your sleep. But now we’re starting to really push forward,” said Cobb. “There’s more literature coming out that sleep can affect more than just mental health. It’s also affecting more comorbidities.”
Cobb clarified that while sleep duration is critical, so is sleep quality, which the current study did not assess. Moreover, the study did not identify the mechanism that leads low-sleep individuals to experience higher risk levels of disease, only that the two are correlated.
Other researchers, such as associate professor of health science at the University of Alabama, Adam Knowlden, have speculated that as a restorative process, sleep promotes hormone production and regulation in the body. This system ultimately helps manage blood pressure, heart rate, and appetite, among other critical functions.
Insufficient sleep can also promote inflammation in the body. While occasional inflammation is normal and healthy, chronic inflation is tied to a host of diseases.
Knowlden believes people need to reframe how they view sleep.
“Often, people see the need to sleep as an inconvenience. They think to get the most out of life, they need to deprive themselves of sleep to get ahead or to be more social, but it’s really the other way around… Most of the research shows your quality of life actually improves if you get sufficient sleep,” he said.
Knowlden recommends a dark and quiet room coupled with a consistent schedule to improve sleep. Caffeine and alcohol should be avoided, as should large meals close to bedtime.
