Taking short naps is the secret to happiness, say scientists.
They have coined a word to describe the contented state after a brief doze — nappiness.
The sleeping habits of more than 1,000 people were measured against how they felt.
Researchers found a clear link between happiness and those who took short naps, compared with those who had longer snoozes or those who never napped.
Psychologist Richard Wiseman, a professor at Hertfordshire University, said: “Previous research has shown naps of under 30 minutes make you more focused, productive and creative.”
“These new findings suggest you can also become happier by just taking a short nap.”
“But longer napping is associated with health risks and, again, this is in line with our results.”
The study, conducted for the Edinburgh International Science Festival, which begins tomorrow, found 66 percent of short nappers — those who slept for under 30 minutes at a time — reported feeling happy.
The figure was 56 percent in long nappers and 60 percent in those who never took a nap.
Researchers also found 43 percent of those aged 18 to 30 took long naps during the day, compared with just 30 percent of those over 50.
Wiseman added: “Short naps boost performance and highly successful companies such as Ben & Jerry’s and Google have installed dedicated nap spaces.”
A separate NASA study of military pilots found a 26-minute nap while the co-pilot was in control boosted alertness by 54 percent.
But frequent hour-long naps are associated with an 82 percent increase in heart disease risk.