Parents worrying about when their kids go to sleep may be justified, according to a new study in the journal Pediatrics.
Researchers found that 7-year-old children with nonregular bedtimes had more behavioral difficulties than children who had regular bedtimes. The good news is that in most cases the effects of a nonregular routine are reversible. That means if your child wants you to read her just one more book, or he wants to finish the end of that TV show, it’s best to say no.
Part of the problem is what a child does before he or she goes to sleep. According to the study, children with late and nonregular bedtimes were more likely to skip breakfast, not be read to daily, and have a TV in their bedroom, and they spent more time (0.3 hours per day) watching TV than did children with earlier bedtimes.
There were also socioeconomic factors, the study revealed:
Children without regular bedtimes and those with bedtimes at 9 p.m. or later had more socially disadvantaged profiles. For example, they were more likely to be from the poorest homes, have parents without degree-level qualifications, and have mothers with poorer mental health. Patterns of parental employment and whether parents felt they had enough time with their children did not vary much across bedtime categories.
Children were sampled from the Millennium Cohort Study, a study of infants born in the United Kingdom between September 2000 and January 2002 were the subjects. Children with autism, Asperger syndrome, and ADHD were excluded from the study.
Questions were not asked about bedtimes on weekends.
Among children who changed from not having regular bedtimes to having them, there were clear improvements in behavioral scores. There was weaker evidence for the reverse — a child’s behavior worsening when going from having a regular bedtime to not having one.
According to the study, not having a regular bedtime might affect children’s behavior in two ways: via disruptions to circadian rhythms, which are slow to adapt to changes in daily schedules, and via sleep deprivation, homeostasis, and brain maturation.
Over time, the study found, this can have profound and lasting effects:
Inconsistent bedtime schedules in the first few years of life might set children onto particular trajectories in relation to their behavioral development, with potential add-on effects for health and broader social outcomes throughout the life course.