The Link Between Napping and Type 2 Diabetes
Could an afternoon nap be harmful to your health? According to a Japanese study, a midday snooze could increase your risk for type 2 diabetes.
In a study from the University of Tokyo led by Dr. Yamada Tomahide, researchers analyzed over 300,000 people and observed their habits and health histories. According to their reports, the finding's indicated that “long daytime naps of more than 60 minutes may lead to a 45 per cent increased risk of Type-2 diabetes, compared with no daytime napping.”
Timing is Everything
While the study seems to show that naps increase our risk for type 2 diabetes, Dr. Tomahide's team did find one interesting loophole: those people who napped regularly for less than an hour a day did not show the same increased risk. “Longer nap was associated with increased risk of diabetes and metabolic syndrome,” the authors concluded, according to the Daily Mail.
This study backs the growing wealth of evidence in favor or short naps, which have been shown to increase alertness and motor skills. As Dr. Tomahide explains, “A short nap finishes before the onset of deep slow-wave sleep... Entering deep slow-wave sleep and then failing to complete the normal sleep cycle can result in a phenomenon known as sleep inertia, in which a person feels groggy, disoriented, and even sleepier than before napping.”
Not a Cause, But a Symptom?
Of course, this study does have its critics. Naveed Sattar, a Professor at the University of Glasgow, has said that napping might not increase a person's risk for diabetes, but actually is a symptom of the disorder.
“It's likely that risk factors which lead to diabetes also cause napping,” Sattar told the BBC. “This could include slightly high sugar levels, meaning napping may be an early warning sign of diabetes.”
Dr. Gerald Bernstein, a coordinator of the Friedman Diabetes Program at Lenox Hill Hospital in New York City, also agrees with Sattar's assessment. While he agrees that napping can cause blood sugar to rise, he's said that the naps will likely only trigger diabetes in people who are already predisposed to the condition.