There’s nothing wrong with a little afternoon nap, right? Well, it seems that may not necessarily be right, according to a new study. As much as you might love catching a few winks of sleep after lunch, there appears to be a link between naps and a risk of several adverse health conditions, including obesity and high blood pressure.
But before you abandon the idea of a daytime nap completely, there’s some good news wrapped up in the study. If your nap length comes in at less than 30 minutes, those risks are reduced. In fact, a nap that comes in under the half-hour mark may well be improving your health.
Untangling the good from the bad when napping is the focus of a new study published in the journal Obesity.
Researchers from Brigham and Women’s Hospital in Boston assessed more than 3000 adults in the Mediterranean. They looked specifically at Spain, arguably the ‘siesta capital’ of the world.
Of the cohort they studied, 35 per cent regularly took siestas, and 16 per cent took ‘long siestas’. The definition of a long siesta in the study was any nap lasting longer than 30 minutes.
The study revealed an association between these long nappers and several adverse health indicators. These include higher values of BMI, waist circumference, fasting glucose, systolic blood pressure and diastolic blood pressure.
That group was also more likely to suffer from metabolic syndrome (MetS). Metabolic syndrome is a collection of conditions, often occurring together that increase your risk of diabetes, stroke and heart disease.
Chicken or egg?
While this study has established links between longer naps and some of these health problems, causality was not resolved. For instance, the results pointed towards the number of cigarettes smoked per day as a factor.
Professor Becca Krukowski, from the University of Virginia School of Medicine, added further context. Prof. Krukowski says it is possible that the longer naps are the result of the health problems, not the other way around. She was not involved in the study.
“However this article adds knowledge about sleep and health risks in a cultural context where napping is encouraged among healthy individuals, across the lifespan, while also considering other potentially related factors, such as nap length and eating patterns.” Prof. Krukowski said.
The power of the power nap
If you love your naps but also want to maintain or improve your health, consider the ‘power nap’. Although further research is required, evidence suggests that a nap of 30 minutes or shorter may confer health benefits.
“Short siestas were associated with a lower frequency of elevated blood pressure compared with [having] no siesta,” the researchers said. Their results indicated a frequency reduction of as much as 21 per cent.
So what can we take away from this research? The long and the short of it is that naps can be good for you, provided they’re short, not long!
As with most things to do with health, adding a power nap to your schedule will likely be only part of the puzzle. Your best chance of improving your health will come from changing other lifestyle factors such as diet and exercise.
Still, this new research provides plenty of food for thought, and may be worth sleeping on. But if you sleep on it during the day, you’d best make sure it’s for no more than 30 minutes!
Also read: Should you see a doctor about bad sleep?