Ensuring children get enough sleep can improve attention and memory while decreasing their risk of obesity and depression, according to new research from the American Academy of Sleep Medicine, which has issued its first guidelines detailing just how much sleep is enough.
The guidelines, which appeared on Monday in the Journal of Clinical Sleep Medicine, say teenagers should get at least eight hours of sleep a day, while infants should have as much as 16 hours.
Wendy Hall, a professor in the school of nursing at the University of British Columbia and the only Canadian member of the research panel, said the guidelines are particularly important because many studies have shown the negative consequences for children who do not sleep enough.
A team of 13 sleep-medicine experts reviewed 864 scientific articles about the relationship between sleep duration and children's health. The guidelines took seven to eight months to complete, Dr. Hall said.
"It's not the case that anything goes with children's sleep," Dr. Hall said. "I think the idea was if we created this really rigorous process and really reviewed all of these papers and had these people come together, that we could make recommendations that were based on the evidence and had really sound evidence to support them."
The guidelines say infants four to 12 months old should sleep 12 to 16 hours a day; one- and two-year-olds should get 11 to 14 hours; children aged three to five should get 10 to 13 hours; six- to 12-year-olds should get nine to 12 hours; and teenagers between 13 and 18 should get eight to 10 hours.
According to the research, children who meet these guidelines are more likely to have improved attention span, memory, emotional regulation, behaviour, and mental and physical health.
Failure to get adequate sleep could result in learning and behavioural problems, as well as increased risk of injuries, obesity, diabetes and depression, the research found. Teenagers who do not regularly meet these requirements have an "increased risk of self-harm, suicidal thoughts and suicide attempts," the report says.
But those who sleep more than the recommended hours may see negative effects, too, ranging from hypertension to diabetes to obesity and mental-health problems, the study says.
Parents can take steps to ensure their children sleep for an appropriate amount of time, Dr. Hall said.
She recommends children school-aged and younger be put to bed by 9 p.m., because those who are not do not sleep as long or as well.
Establishing regular bedtime routines and keeping cell phones and games out of children's sleep environments can also help them sleep more easily and have an overall better quality of sleep, she said.
"It goes a long way towards promoting children's sleep because they're less likely to be awake in the night and answering texts or checking things online," Dr. Hall said.
"Also, if they diminish their exposure to those things … at least a couple hours before bedtime, it means the blue lights from the screens are not interfering with children's natural melatonin secretion, which helps them get ready to go to sleep at night."