Late nights 'sap children's brain power'

Sleepy boy Late nights may have knock-on effects

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Late nights and lax bedtime routines can blunt young children's minds, research suggests.

The findings on sleep patterns and brain power come from a UK study of more than 11,000 seven-year-olds.

Youngsters who had no regular bedtime or who went to bed later than 21:00 had lower scores for reading and maths.

Lack of sleep may disrupt natural body rhythms and impair how well the brain learns new information say the study authors.

They gathered data on the children at the ages of three, five and then seven to find out how well they were doing with their learning and whether this might be related to their sleeping habits.

Start Quote

Establishing a good bedtime routine early in childhood is probably best, but it's never too late”

End Quote Study author Prof Sacker

Erratic bedtimes were most common at the age of three, when around one in five of the children went to bed at varying times.

By the age of seven, more than half the children had a regular bedtime of between 19:30 and 20:30.

Overall, children who had never had regular bedtimes tended to fare worse than their peers in terms of test scores for reading, maths and spatial awareness.

The impact was more obvious throughout early childhood in girls than in boys and appeared to be cumulative.

The researchers, led by Prof Amanda Sacker from University College London, said it was possible that inconsistent bedtimes were a reflection of chaotic family settings and it was this, rather than disrupted sleep, that had an impact on cognitive performance in children.

"We tried to take these things into account," said Prof Sacker.

The children with late and erratic bedtimes came from more socially disadvantaged backgrounds and were less likely to be read to each night and, generally, watched more TV - often on a set in their own bedroom.

After controlling for such factors, the link between poorer mental performance and lax bedtimes remained.

The findings are published in the Journal of Epidemiology and Community Health.

Prof Sacker said: "The take-home message is really that routines really do seem to be important for children.

"Establishing a good bedtime routine early in childhood is probably best, but it's never too late."

She said there was no evidence that putting children to bed much earlier than 19:30 added anything in terms of brain power.

Dr Robert Scott-Jupp of the Royal College of Paediatrics and Child Health said: "At first glance, this research might seem to suggest that less sleep makes children less intelligent, however, it is clearly more complicated than that.

"While it's likely that social and biological brain development factors are inter-related in a complex way, in my opinion, for schoolchildren to perform their best, they should all, whatever their background, get a good night's sleep."


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  • rate this

    Comment number 370.

    Not everyone is built to go to bed at the same time. I have been an 'owl' my whole life - my natural bedtime is between about 3am, and my natural waking time is about 11am.

    The biggest problem with being an 'owl' is that most people simply refuse to believe it's not an act. It's not, and stories like this one do not help.

    Oh, and I always did extremely well in reading and maths.

  • rate this

    Comment number 369.

    Unfortunately the parents who need to learn this valuable information don't read or watch the news, and will be in the pub till 12ish whilst their beloved offspring run riot.

  • rate this

    Comment number 368.

    It would be an interesting experiment to let children go to bed whenever and for how long they want.
    "You know, every night when we're wide awake she makes us go to bed,
    And then in the morning when we're fast asleep she makes us get up."
    - Terry Scott, "My Brother".
    This exactly matches memories of my own childhood and seemingly comment #45 as well.
    Today I'm more of an 'owl' than a 'lark'.

  • rate this

    Comment number 367.

    Any research been done on variation of sleep need with season. Surely our primitive ancestors will have made maximum use of longer day length in summer (less sleep) but may have been more inclined to hole up and maximize sleep in winter? Just athought.

  • rate this

    Comment number 366.

    Why do we pay people to come up with the blindingly obivous ?

  • rate this

    Comment number 365.

    DO NOT DO HOMEWORK! it amazes me that educated, intelligent, articulate strong people are saying . 'by the time the 5 YEAR OLD!!' does homework' etc who is the boss in your home?? i have 3 teens not one of them did ANY homework at primary i absolutely refused it. we played had a bath tea stories then bed. homework in primary is bunkum, what are the school going to do! secondary yes. All 3 fine!

  • rate this

    Comment number 364.

    Perhaps kids are happier to go to bed if its not school the next day.

  • rate this

    Comment number 363.

    Wow! Sleep-derpived children do worse at school? Really? I'm so glad someone did a study to find this out!
    In all seriousness though, it can be hard to get children to sleep if they're not tired, especially when they don't get enough exercise during the day. In this case it's best to put them to sleep with a book to read.
    Children should NEVER have a TV in their room. That's horrific.

  • rate this

    Comment number 362.

    358. Harold
    Fully agree. How can we move on if we can't look at the real issues?
    I'm sure I've sometimes written awful rubbish, but here I did try to list some solutions, 354 and also an hour ago -where I got minus 3 points,
    Many Britons know Germany, Scandinavia, have fewer parenting problems- due to magic, as I rarely hear anyone ask why, or what we could do.

  • rate this

    Comment number 361.

    I've been going to bed at random times for the past few years, the only thing that EVER hindered my education/learning power was the TEACHERS.

    At school I was forced to do 3-4 hours of homework per day, I could've gone to sleep whenever and still not been happy/able to do that much.

    I went to college and excelled, yes, there was a great deal of work, but the tutors were happy to teach/answer.

  • rate this

    Comment number 360.

    This applies to adults too. When looking about my office, I can tell which ones have been out clubbing all night and lost sleep, they're the ones with the blunt minds and half-closed eyes. I figured that out without wasting my time at University.

  • rate this

    Comment number 359.

    Some scarily militant opinions here! My parents were very relaxed about bedtime (having 8 children likely contributed).

    I accept 3 year olds might be a tad young, but being responsible for sleep taught me a valuable lesson regarding action and consequence. Didn't do this doctor too much harm...

    I suspect the study has more to do with disruptive home life rather than sleep quality per say...

  • rate this

    Comment number 358.

    Mainly an article about common sense.

    Forty-nine up votes for the assumptions of a delivery driver... you couldn't make it up!

  • rate this

    Comment number 357.

    It is obvious really that it is not a 'one size fits all' issue! My two were at full time day nursery at five months old - before separation anxiety at ~ seven months - so they loved it from the start and always ran happily in and happily out when collected! BUT they and we loved our time together in the evenings and we have never wanted rid of them but valued their company; we had no TV then!

  • rate this

    Comment number 356.

    Somebody got paid to do this study? I wonder why - after all, if sleeping discipline has been getting worse, how come grades have been on the rise and universities are overflowing with talented youngsters.

    More like somebody on the research grant gravy train having a laugh.

  • rate this

    Comment number 355.

    I think this study is flawed. The problems with childrens congitive abilities is more about discipline than bed time. The lack of a consistent bedtime is just one of the results of the lack of discipline and structure in their lives. There are other studies that suggest children who can't go to sleep early are more intelligent than others. It's quite silly.

  • rate this

    Comment number 354.

    True, parents are to blame but most European countries do more.

    Eg. equal access to quality education, funded alternatives so there's real choice, funded after school activities, free breaks for stressed mums +child care, plus well funded, rounded, teacher-run state schools.
These help level the playing field, develop responsibility, and, so, better parents.

  • rate this

    Comment number 353.

    @ 315 buddy

    To concerned at criticism of and from parliament and government.

  • rate this

    Comment number 352.

    Let parents work out how much sleep their child wants. Miine never wanted more than 8 hours sleep even as a baby - we always had a routine and still do with the telly going off at 10.00 Is now in year 9 and has just got an a in her maths gcse mock exam and is one of the brightest children in her year

  • rate this

    Comment number 351.

    Am I missing something? Is there somewhere in this report that states it is mandatory to put your child to bed at 7.30pm? Or 9pm? By the reaction of some people (mostly parents by their posts) you'd think the bedroom police were on the way!


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