• Mayo Clinic Q and A: Teens can concentrate, learn and think better when well-rested

teenage girl sleeping, wrapped in blankets

DEAR MAYO CLINIC: How much sleep should teenagers be getting, and how does it affect their health if they are sleep deprived? My daughter is 16 and only sleeps about six hours each night during the week. She says she isn’t tired and makes up for it by sleeping in on the weekends, but I am worried it’s affecting her ability to concentrate at school.

ANSWER: You’re right. Your daughter needs more sleep. To be well-rested and to help them stay healthy, teenagers need about nine to nine-and-a-half hours of sleep each night.

Healthy sleep is important for many reasons. It can fight stress, improve mood and attitude, and provide energy. When teens are well-rested, they can concentrate, learn, listen and think better than when they’re tired. That can improve school participation and performance. Healthy sleep also contributes to a healthy body, helping it run the way it should.

Unfortunately, many teens don’t get the sleep they need. One of the big reasons is that the body’s internal clock shifts during the teen years. In the preteen years, the hormone melatonin, which signals to the body that it’s time to sleep, is released into the bloodstream earlier in the evening. In most teens, melatonin levels don’t rise until about 10:30 or 11 p.m., so they aren’t sleepy before then. But going to bed at that time means teens should ideally sleep until about 7:30 or 8 a.m. This isn’t an option for many because schools often start earlier than that.

More than others, some teens tend to show a preference for the late evening hours. They are actually most energetic, intellectually productive and creative in the late evening (night owls). It is important to recognize that this is also a normal pattern. For those with a “night owl” tendency, however, it is especially important to provide lots of light exposure and physical activity immediately upon awakening in the morning and to have dimmer lighting around the house during the evening hours.

One of the most important things teens can do to sleep well regularly is to set a consistent wake-up time and build a sleep schedule around it. It doesn’t have to be exactly the same, but the wake-up time should be within about a two-hour window every day of the week. This allows the body’s internal clock to run smoothly and avoid the difficulty of trying to readjust and get up on Monday morning at 6 a.m. after sleeping in until noon on the weekends.

Picking a reasonable bedtime and sticking to that most days can be very useful, too. When a teen gets up at the same time every day, they will get sleepy around the same time every night. Your daughter should listen to that and go to bed as soon as she feels tired.

After-school jobs, if they are too time-consuming, may lead to a significant amount of lost sleep. If your teen has a job, consider limiting it to no more than 15 hours a week. Then it’s likely she’ll still have enough time for homework and other activities without sacrificing sleep.

There are also ways your daughter can make it easier for her body to sleep. For example, stay away from pop, sugar, caffeine and big meals two to three hours before going to bed. Exercise, but do it at least two hours before bedtime. Don’t nap during the day.

Creating a sleep-friendly environment can make a difference, too. Electronic devices and screens, along with the lights on them, in a teen’s room at night often disrupt sleep. Avoid distractions by keeping TVs and computers out of bedrooms. Cell phones should be turned off at bedtime and stored outside the bedroom. For the best sleep, keep bedrooms cool, dark and quiet during the night.

Encourage your daughter to get more sleep each night. When she does, it’s quite likely that she’ll feel more alert, have more energy and be able to focus more effectively and for longer periods of time at school. Suresh Kotagal, M.D., Center for Sleep Medicine, Mayo Clinic, Rochester, Minn.

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