Finding your aging parents napping frequently early in the day could be a warning sign of something much more serious, doctors at Boston’s Mass General Brigham healthcare system have warned.
While quick cat naps can often be restorative, previous research has shown that longer naps can negatively impact cognitive ability and cardiovascular health.
Now, a new, nearly two-decade-long study of more than 1,330 people reinforces and builds on those findings, showing that longer and more frequent morning naps are tied to a higher risk of death and underlying illness.
Although the researchers did not say if there was a critical threshold for how many naps were too many naps to take, they found that each additional hour of napping was tied to a 13 percent higher risk of death and each extra nap raised that risk by 7 percent. Morning nappers had a 30 percent higher mortality risk compared to afternoon nappers, too.
The findings could help children identify when there’s something seriously wrong with their loved ones, potentially leading to earlier treatment.
“It is important to note that this is correlation not causation. Excessive napping is likely indicating underlying disease, chronic conditions, sleep disturbances, or circadian dysregulation,” Dr. Chenlu Gao, the lead author of the study, said in a statement.
“Now that we know there is a strong correlation between napping patterns and mortality rates, we can make the case to implement wearable daytime nap assessments to predict health conditions and prevent further decline,” he added.
The researchers used wearable devices to track the health of the study’s participants, although the participants reported how much physical activity they got and any underlying health conditions.
The researchers took their data from the 1997 Rush Memory and Aging Project, which included mainly white individuals over the age of 56 in northern Illinois.
Participants of the project wore wrist activity monitors for 10 days to measure their rest in April 2005 and repeated the practice every year for 19 years.
That’s how the Mass General Brigham researchers were able to determine their sleep patterns, mapping out when and how long the older adults napped.
They did not factor in the quality of the naps or the difference between racial groups or shift workers, and said more research was needed to understand the impact of irregular napping.
But they have some ideas about the physiological processes tying excessive napping to an increased risk of death.
Inflammation, underlying sleep disorders and fatigue-causing chronic health conditions may all increase the risk of death and excessive napping, they said.
“Many chronic health conditions can cause fatigue and excessive sleepiness and prompt napping as a coping mechanism, including chronic lower respiratory diseases, chronic pain, diabetes, cardiovascular conditions, metabolic syndrome, mood disorders, and neurodegeneration,” the researchers wrote.
Until now, Gao said, how napping patterns were tied to health had been understudied, although the researchers had previously found a link between excessive naps and Alzheimer’s disease in 2022.
“Our study is one of the first to show an association between objectively measured nap patterns and mortality and suggests there is immense clinical value in tracking napping patterns to catch health conditions early,” he said.
Between 20 and 60 percent of older adults take naps, the researchers say.
Naps are best kept to 15-20 minutes for adults, according to the Cleveland Clinic. But most people should limit their shut-eye to under an hour.
And the best time to nap is earlier in the afternoon, before 2 to 3 p.m., so you can still fall asleep at night.
“If you need to nap, try to limit it to up to 30 minutes,” Dr. Suzanne Salamon, associate chief of gerontology at Harvard-affiliated Beth Israel Deaconess Medical Center, explained in a statement. “A little napping is normal as we get older, and quick catnaps can recharge your batteries. It’s a lot of napping that we worry about.”
