Most parents have faced a grumpy child who refuses to go to bed.
But letting them stay up just a bit longer could damage their performance at school, says an expert on child development.
Parents should stick to one fixed time, because their child’s reading and maths could suffer, warns Dr Yvonne Kelly from University College London.
She told the World Sleep Society that seven-year-old girls and three-year-olds of both sexes perform less well in tests if they do not have a regular bedtime.
Allowing children to stay up just a bit longer could damage their performance at school, says an expert on child development (file photo)
Her findings also show that three-year-old children are worse at regulating their emotions and more likely to be obese in later life if they do not go to bed at the same time each night.
She says children can suffer ‘jet lag’ from going to bed at different times every day. ‘It is important that children go to bed at a fixed time so they can maintain their circadian rhythms,’ she said.
‘If you fly across time zones, it is difficult to function when you get to New York, for example.
‘If you ask a child to effectively do the same thing by changing their sleeping patterns, they are going to struggle even more than an adult would.
‘Sleep is important for forming and storing memories, to learn from day to day, and it is essential for children.’
Dr Kelly’s warning follows four years of research. In a study of more than 11,000 children, published in the British Medical Journal, a team led by her found three-year-old children performed worse in tests of spatial awareness, reading skills and mathematics without a set bedtime.
Parents should stick to one fixed time, because their child’s reading and maths could suffer, warns Dr Yvonne Kelly from University College London (file photo)
Girls did worse in all these areas at the age of seven, although boys appeared unaffected. She has also found children with irregular bedtimes are more likely to be badly behaved than their peers.
But there can still be a happy ending for worried parents.
Writing on website The Conversation, Dr Kelly said: ‘We did find an important piece of good news, too – those negative effects on behaviour appeared to be reversible.
‘Children who switched to having a regular bedtime showed improvements in their behaviour. This shows that it’s never too late to help children back onto a positive path, and a small change could make a big difference to how well they get on.’