Parents, teachers and doctors all agree that lack of sleep makes children cranky, tearful and more prone to tantrums. Now researchers from the UK have found that children with irregular bedtimes are more likely to have behavioral difficulties.
The study, published in the journal Pediatrics, found that irregular bedtimes could disrupt natural body rhythms and cause sleep deprivation, undermining brain maturation and the ability to regulate certain behaviors.
Adopting a regular bedtime routine is probably the first thing an adult with sleep problems would be advised to do. And the same applies to children. Following a routine helps train behavior and a nighttime routine helps your child learn to be sleepy.
Professor Yvonne Kelly, from University College London's department of UCL Epidemiology & Public Health, says:
"Not having fixed bedtimes, accompanied by a constant sense of flux, induces a state of body and mind akin to jet lag and this matters for healthy development and daily functioning."
She explains further:
"We know that early child development has profound influences on health and wellbeing across the life course. It follows that disruptions to sleep, especially if they occur at key times in development, could have important lifelong impacts on health."
Analyzing data from more than 10,000 children in the UK Millennium Cohort Study, the team collected bedtime data at 3, 5 and 7 years, as well as incorporating reports from the children's mothers and teachers on behavioral problems.
Clear link between bedtime and behavior
Although inconsistent bedtimes can adversely affect a child's behavior, the study shows that the changes are reversible - once a regular routine is established, the child's behavior settles down.
The study found a clear clinical and statistically significant link between bedtimes and behavior. Irregular bedtimes affected children's behavior by disrupting circadian rhythms (body clock), leading to sleep deprivation that affects the developing brain.
As children progressed through early childhood without a regular bedtime, their behavioral scores - which included hyperactivity, conduct problems, problems with peers and emotional difficulties - worsened.
However, children who switched to a more regular bedtime had clear improvements in their behavior.
Prof. Kelly says:
"What we've shown is that these effects build up incrementally over childhood, so that children who always had irregular bedtimes were worse off than those children who did have a regular bedtime at one or two of the ages when they were surveyed."
"But our findings suggest the effects are reversible," continued Prof. Kelly. "For example, children who change from not having to having regular bedtimes show improvements in their behavior."
Irregular bedtimes and fewer hours of sleep
Irregular bedtimes were most common at the age of 3, when around 1 in 5 children went to bed at varying times. However, by the age of 7, more than half the children went to bed regularly between 7.30 and 8.30 pm.
Children whose bedtimes were irregular or who went to bed after 9 pm came from more socially disadvantaged backgrounds, and this was factored into the study findings.
Prof. Kelly says:
"As it appears the effects of inconsistent bedtimes are reversible, one way to try and prevent this would be for health care providers to check for sleep disruptions as part of routine health care visits. Given the importance of early childhood development on subsequent health, there may be knock-on effects across the life course. Therefore, there are clear opportunities for interventions aimed at supporting family routines that could have important lifelong impacts."
Most parents would agree that consistency is key to bringing up children, and the same rules seem to apply to bedtimes. Although no two children will be exactly alike in their sleep requirements, keeping bedtimes regular and with a consistent routine will show improvements in bad behavior.
When asked by Medical News Today if irregular bedtimes also lead to poor academic performance, Prof. Kelly agreed, pointing to research published in the Journal of Epidemiology & Community Health. Tying this study in with the previous research, she said:
"Children with irregular bedtimes went to bed at varying times - night to night. We know from other studies that irregular bedtimes correlates with fewer hours of sleep."