When school lets out for the summer, even the strictest parents can get a little lax about enforcing bedtimes, especially if it's still light outside when it's time to start putting younger children to bed.
But research has shown that regular sleeping schedules are important for health and that children fare better physically and emotionally with consistent bedtimes. For that matter, their parents do, too.
Going to bed and getting up at a set time that rarely changes is often the first advice that experts give to people having sleep issues. A regular bedtime is associated with being able to fall asleep more easily, feeling refreshed upon awakening, and even being able to stay asleep all night. Children (and even college students) who have consistent bedtimes perform better in school. They behave better at home. And one recent study even suggests that when parents enforce a regular schedule, their children are less likely to become obese in adolescence.
The next time someone says "Please, just a little bit later" in your household, here are a few things to consider before giving in to the plea.
Child psychologist John Rosemond said bedtimes are more for parents than for children. But aside from giving adults in the household some quiet and grown-up time, children benefit from regular bedtimes that are strictly enforced.
"Concerning sleep and youngsters, the general rule is that the later a young child stays up at night, the less well the child will sleep. Being overtired is the biggest cause of sleeplessness and restless sleep in small ones," Rosemond wrote in his syndicated parenting column.
Jodi Mindell, a pediatric sleep specialist in Philadelphia, said the consequences of late bedtimes for young children include hyperactivity and emotional dysregulation. In a paper Mindell co-authored, she said the standard treatment for children with insomnia and other sleep problems includes the establishment of a consistent sleep schedule, but the schedule should be tailored to the child's age. After puberty, she noted, children's circadian rhythms shift by about two hours, so bedtimes should be adjusted as children get older.
But the body's natural patterns of sleep and wakefulness can be interrupted earlier in childhood and result in a condition known as circadian rhythm disorder. The problem can be the result of travel across time zones, medication use or simply changes in routine, like those that occur in summer.
In a study published last month in the International Journal of Obesity, a team of researchers analyzed the health records of nearly 11,000 children in the United Kingdom to see if there is a connection between family habits in early childhood and the children's health as they entered adolescence.
The researchers looked at the prevalence or absence of three practices: regular bedtimes and mealtimes and limits on watching TV. Greater adherence to a routine at age 3, as well as restrictions on screen time, seemed to result in children who were better able to self-regulate their behavior.
Of all those family practices, the lack of a regular bedtime seemed to have the most effect on children who were obese later, writer Jeff Nesbit reported for U.S. News & World Report.
"The research showed that the absence of a regular preschool bedtime routine is an independent predictor of obesity at 11. The risk of obesity was greatest for those with the least amount of consistency in their bedtimes, compared to those who always had a regular bedtime," Nesbit wrote.
Sarah Anderson, the lead author, was also involved in an earlier study that showed similar results among American children. That research, published last year in the Journal of Pediatrics, also relied on parents' recollections of their family habits, but it found that preschool children with early bedtimes were half as likely to be obese in adolescence as those who went to bed later.
The research only shows an association between late bedtimes and obesity, not that staying up late causes weight gain. And parents who enforce bedtimes may also be more likely to enforce healthy eating habits.
But Anderson noted that poor or abbreviated sleep is associated with an increased risk of obesity at all ages. "Bedtimes have a greater impact on children's sleep duration than do wake times" and are more easily modified, Anderson and her co-authors wrote in the study, which concluded by urging pediatricians to encourage parents to adopt early bedtimes in their households.
The reasons could include a decline in self-regulation that is associated with children who grow up without routines, but there could be biological factors at play. Scientific American reported on research that showed an association between sleep deprivation and increased food consumption.
And according to the National Sleep Foundation, fewer than half of American children get the amount of sleep their pediatricians recommend, a problem exacerbated by early school start times and electronics in the bedroom.
Even among adults, regular sleep patterns can be difficult to maintain. A recent survey of 4,000 people in America and England conducted by YouGov for the meditation app Calm.com found that 46 percent found it difficult to sleep on Sunday nights.
Steve Orma, a clinical psychologist and insomnia specialist, said in a USA Today article that the most likely cause of Sunday-night insomnia is that people don't go to bed at their usual times on Friday and Saturday nights and then tend to sleep later on weekend mornings, which throws their schedule off.
According to the survey, the night people slept the best was Thursday, which could be the result of having several consecutive days of a set bedtime. In one small study of 32 children ages 8-12, children who went to bed earlier for just four nights had better memory and attention than children who went to bed one hour later.
The American Academy of Pediatrics and the American Academy of Sleep Medicine agree on guidelines parents can consult when determining how much their children should be sleeping. They are:
Infants 4 months to 12 months — 12 to 16 hours (including naps) every 24 hours
Ages 1-2 — 11 to 14 hours, including naps
Ages 3-5 — 10 to 13 hours, including naps
Ages 6 to 12 — 9 to 12 hours
Ages 13 to 19 — 8 to 10 hours
The academies do not advise parents on what time to put their children to bed, saying only that those hours of sleeping should occur "on a regular basis." But the National Sleep Foundation says its research has shown that children who go to bed after 9 p.m. take longer to fall asleep, wake more often at night and get less overall sleep.
Parents have to set bedtimes that work for their schedules and jobs, but when making that decision, they might want to consider the experience of Melinda Wenner Moyer, a New York science writer and parenting advice columnist. Writing for Slate, Moyer said she puts her preschoolers in bed before the sun sets — even in summer — and says they've been happier on the rigid schedule.
"Ever since I've started looking at the science, I've become only more convinced that the earlier you say night-night, the better," she wrote.
To find the ideal time for her children, Moyer followed the advice of a friend, sleep consultant Arielle Driscoll, who recommends putting children to bed 20 minutes earlier than usual and seeing what happens.
You may have to tinker with the schedule for a while to get the right time for your family. But whatever that perfect time is, it's best not to alter it much during the summer if you want well-rested, healthy children.
Also, allowing your children to turn into what Today.com called "summer zombies" will make life more difficult in the fall.
"If kids get in the habit of sleeping until noon, it can take weeks to get back on schedule when school starts," sleep specialist and author Malia Jacobson told Today.