- Napping for more than 30 minutes at a time can raise the risk of diabetes, according to a new study
- It can also increase likelihood of high blood pressure and high cholesterol
19:04 EST, 20 September 2013
19:14 EST, 20 September 2013
They were much favoured by Margaret Thatcher, Albert Einstein and Winston Churchill.
But while afternoon naps may revitalise tired brains, they can also increase the risk of diabetes, according to new research.
A study of more than 27,000 people in China – where taking a post-lunch snooze is very popular – shows napping for more than 30 minutes at a time can raise the chances of developing type two diabetes.
Researchers found men and women taking 40 winks were also more likely to have high blood pressure and raised cholesterol levels compared to those who stayed awake through the day.
Napping for more than 30 minutes at a time can raise the chances of developing type two diabetes, according to a new study
The findings, published in the journal Sleep Medicine, are in contrast to those from other recent studies, which found daytime sleeps could boost brain power and slash the risk of heart attacks and strokes by more than a third.
The researchers said it’s the duration of the nap that counts. Those dozing for half an hour or more were more likely to have the early signs of diabetes than those who snoozed for less time or not at all.
In 2009, a planned UK National Siesta Day was cancelled when similar research from China found a 26 per cent increase in diabetes risk among those regularly getting their heads down in the afternoon.
Diabetes affects an estimated 2.5 million people in the UK. Around ten per cent of cases are due to type one, which is thought to be caused by a malfunctioning immune system and has nothing to do with diet.
Diabetes affects an estimated 2.5 million people in the UK, with around ten per cent of cases due to a malfunctioning immune system. Above, a woman tests her blood sugar (file pic)
But the remaining 90 per cent are type two, closely linked to unhealthy diet and lifestyle.
The body loses its ability to make use of glucose, a type of sugar that is released when we eat food and turned into a source of energy for use by muscles.
As glucose levels rise, circulation starts to suffer and blood vessels in areas such as the heart, the legs and the eyes can be irreparably damaged.
In the latest study, researchers at the Huazhong University of Science and Technology in China studied 27,009 men and women aged 45 or over.
Former Prime Minister Margaret Thatcher was famously known for napping
Almost 70 per cent of the volunteers said they regularly took a nap in the afternoon.
Researchers checked their health by carrying out a test called impaired fasting plasma glucose.
This measures whether sugar in the blood is too high and acts as an early warning sign that type two diabetes is setting in.
Researchers also looked to see which volunteers were in the early stages of the disease.
They found glucose readings were much higher among those who favoured a daytime sleep.
Forty per cent of them also had high blood pressure, compared to just 33 per cent of non-nappers, and 24 per cent had high cholesterol, versus 19 per cent.
One reason a siesta may be harmful is it simply means less exercise is being undertaken, the researchers said.
But it could also be that it disrupts the body’s internal clock and exposes organs to higher levels of the stress hormone cortisol.
In a report on their findings the researchers said: ‘Napping in the elderly can be beneficial for daytime functioning, as well as for mental health.
‘But there is accumulating evidence showing it may also be a risk factor for morbidity and mortality.’
Dr Matthew Hobbs, head of research for Diabetes UK, said there was no proof that napping actually caused diabetes.
He said: ‘The bottom line is that the best way to reduce your risk of type two diabetes is to maintain a healthy weight by eating a healthy, balanced diet and by being regularly physically active.’
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The comments below have been moderated in advance.
My dad and grandfather took a nap every day. Neither one ever had health problems. This study sounds like it was staged.
tucson, United States,
Where do you people get these study ideas? Is there anything you are not studying? If we believe all these studies we will find that everything we do is bad for us and everything we do not do is what is good for us. The egg is bad, no the egg is good, napping of all things being deadly is the last straw. How come sleeping at night doesn’t kill us too? Oh wait, we snore!
Windham, United States,
What a load of cobblers if was good enough for Maggie,Albert and Winnie then it is good enough for me,i love my afternoon naps.I am retired and no i do not have diabetes,high blood pressure or high cholesterol but i do exercise a lot.
Correlation does not equal causation. Likely,the people who take naps are less fit, less healthy and take naps because of these health issues.
I think you’ll find you have ’cause’ and ‘effect ‘ the wrong way round here……
Huddersfield, United Kingdom,
nooooo….I like having a nap
I guess that I am okay, as I have never taken a nap in my life. I can only sleep in a bed at night, however tired I might be.
Maybe they are already ill and need to nap because of this not the other way around.
Or do people who have a nap are more likely to to have diabetes?
ST Louis Missouri, United States,
Does the nap cause the diseases, or do they nap because they already have early signs of the diseases?
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