Around half of the Dutch population is unhappy with the amount of sleep they get and around a quarter of them are worried about it.

The figures come from a recent survey by the Dutch sleep research foundation NSWO. Of those taking part in the survey, 49% said they are unhappy with their own sleep pattern and 27% said not getting enough sleep worries them.

Just under one-third said they feel sleepy during the day and one-fifth take an afternoon nap, the NSWO says.

Despite this, many of them see no problem in taking a drink containing cafeine just before bed. 12% said they drink cola, 9% drink coffee and one in a 100 drinks an energy drink, the survey shows.

Around half of the men questioned drink alcohol before going to bed and 35% of women. People also watch tv in bed, make phone calls, use internet and check their social media channels, the survey found.

9% of the Dutch often or always take a sleeping pill, with another 27% saying they do so sometimes or seldom.

The survey was conducted for National Sleep Week which continues until Saturday.