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Cranky Teenagers:  Biology and Modern Life can Create the Perfect Storm

 A boy.posing for the camera.

Today’s post comes from a sleep expert about the real reason tweens & teenagers are cranky (and it’s not what you think)

If you’re the parent of a teenager, you’re probably familiar with some grumbling, a little eye-rolling, and an occasional grumpiness.  Sometimes it’s out of the blue and usually- it’s out of character for your child.   Don’t worry… there is a reason.

Important biological changes are taking place while he’s also trying to navigate the realities of teenage life that often leave him sleep-deprived. The effects of sleep deprivation may be getting in the way of not only your teen’s ability to regulate his emotions but also of his ability to reach his full potential.

Biology Takes Its Course

The first step in understanding your cranky teen is knowing what’s happening on the inside. The body uses regular 24-hour cycles called circadian rhythms to control the sleep-wake cycle. Somewhere in the late preteen or early teen years, the adolescent body goes through a fundamental shift in circadian rhythms called sleep phase delay. Rather than feeling sleepy at eight or nine PM, your teen is suddenly wide awake until ten or eleven PM. This change might look like insomnia, but it’s a natural part of adolescence.

The Pressure of Education

At the same time your teen’s body is going through these changes, he will be attending schools with the earliest start times in the school district. Many junior highs and high schools start between seven and eight AM with some classes beginning even earlier.

Early start times can make it hard for your team to get the sleep he needs, especially if he isn’t nodding off until 11 PM. Studies have shown that schools with later start times report improved test performance, as well as a reduction in vehicle accidents amongst students.

The amount and level of difficulty of your child’s homework also go up at this age. He may be spending more time than ever studying and doing homework because his grades now affect his high school transcript and college acceptance.  More studying may mean putting off going to bed far longer than he should.

More Extracurriculars

If your teen participates in extracurricular activities, they may require more time as he gets older. Fundraising, travel, and weekend commitments become commonplace in high school. While it might be easy to say your teen should simplify and cut back on extracurricular activities, colleges often consider extracurriculars when accepting students. The more involved he becomes, the less time he has for sleep

The Beginnings of a Social Life

The teen social life cannot be ignored. Many teenagers start to spend more time with friends than ever before. Today, the teenage social life extends beyond physically spending time with friends. Many teams spend hours “socializing” by text and through social media. That time can easily cut into sleep time.

Why Children are less patient & more lonely than ever before

A Sleep-Depriving Combination

The combination of biological changes, educational requirements, extracurricular pursuits, and social life leave little time for sleep in the life of many teens (Don’t forget, some teens may also be juggling a part-time job). But teens still need a good eight to ten hours of sleep to function at their best.

Without adequate rest, the body and brain start to slow down and change how they function. Neurons in the brain slow the speed at which they send messages, which slows reaction times, reasoning skills, and decision-making abilities. Short-term memory also takes a hit with sleep deprivation. Without sleep, not only will your teen have a harder time remembering what he’s studied but he won’t be able to learn as effectively. Kids that get better (and more) sleep tend to perform better in core areas such as writing and math.

 Sleep deprivation impacts more than educational performance. Sleep plays a pivotal role in appetite and metabolism regulation. When sleep-deprived, the brain releases more hunger hormone and less satiety hormone, which puts your teen at risk for overeating and unwanted weight gain. Chronic sleep deprivation contributes to obesity that increases the risk of diabetes, heart disease, and high blood pressure.

What to Do and How You Can Help

You can help your teen get the sleep he needs. Parents, teens, and school administrators can work together to develop a school schedule that supports adolescent biology for improved academic performance. You can also help by creating the healthy sleeping conditions in his room. If he’s a back sleeper or a side sleeper, his mattress should be matched to his preference. A comfy bed is a nice step in the direction of better sleep.

But, you’ll also need to help your team develop good habits that will last him a lifetime, such as:

  • A Consistent Bedtime: This is a tough one for teens who like to sleep in on the weekends. However, a consistent bedtime helps establish healthy circadian rhythms. As he keeps a consistent sleep schedule, your child’s body will begin to recognize when it’s time to release sleep hormones. A regular bedtime also assures that he has plenty of time in bed to get the rest he needs.

  • Bedtime Routine: Your teen may think he’s too old for a bedtime routine, but they can do wonders for those who struggle to fall asleep. A routine gives your child a chance to relieve stress and tension. A warm bath, reading a book, or listening to quiet music can all be part of his routine. When performed in the same order at the same time each day, a routine can help the body know when to release sleep hormones.

  • Limit Screen Time: The bright blue light from electronics like the televisions, smartphones, laptops, and iPads can suppress the release of sleep hormones. Teens who are glued to their phones may find it difficult to fall asleep on time. Turning off screens at least two to three hours before bed can help the body maintain a regular sleep-wake cycle.

  • Avoid Stimulants: Although your teen may be convinced he needs an energy drink to stay awake while studying, the caffeine could come back to haunt him. Caffeine and similar stimulants temporarily block sleep hormones. To prevent a delay in the onset of sleep, encourage your teen to stop consuming stimulants at least four hours before bed.

  • Swap Chores for Screentime – This is perfect for a teenager.  They are at a great age to learn about hard work and understanding the “work before play” concept.  Give them jobs to do in order to have time on their phone.  Hold them accountable for things that need to be done.  No Screentime until Chores are done

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Hi there!

I’m Becky, a former elementary school teacher turned certified child development therapist and blogger. I work at home with my husband and together we are raising (and partially homeschooling) our four children in the Carolinas. I love diet coke, ice cream, and spending time with my family.

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