09 Mar, 2022

The Teenage Brain and Sleep

As part of National Sleep Awareness month, we are taking a deep dive into the topic of teenagers and sleep. Why do teenagers act the way they do? How much sleep do they really need? And what are the consequences of not getting enough of it? As you may suspect, good sleep is linked to better emotional health and decision-making, which in turn reduces risk-taking behaviors. Here’s what you need to know about the teenage brain and sleep.

What does brain science say about teenagers and sleep?

Neuroscientists study the brain and how it impacts our behavior. Interestingly, they have found that teenagers have a different internal clock than adults. In her book “The Teenage Brain”, neuroscientist Frances E. Jenson refers to teens as “night owls”. One clear evidence of that phenomenon is that the teenage brain releases the critical sleep hormone melatonin two hours later than adult brains. As a result, teenagers tend to still feel perfectly wired late at night, while adults tend to turn in around 10:00 PM. However, this shift in the internal clock is temporary. It should go back to normal once the teenage stage is over. In the meantime, this finding is relevant when it comes to explaining teenagers’ behaviors and why they seem to be so counterproductive at times. Apart from this internal clock finding, Jenson shares additional insights on the topic of teenagers and sleep. 

How much sleep do teenagers need?

Surprisingly, teenagers actually need more sleep than adults or younger children. This is because teenagers go through puberty, which involves a lot of growth and development. On top of that, they also spend most of their time learning. And when it comes to learning, neuroscientists are in agreement: the more we learn and the more sleep we need. Sleep not only helps us rest physically, but it also allows us to process the information that we acquire during the day, encoding it in our long-term memory during sleep. Taking these two reasons into consideration, studies have measured that teenagers need on average 9 hours and 15 minutes of sleep per night. In reality, we see that only about 15% of them get that amount during the week. On the weekends, however, Jenson points out that things go differently. Without an artificial alarm to wake them up, teenagers tend to sleep in later, according to their biological needs.

What happens when teenagers don’t get appropriate amounts of sleep? 

As we mentioned above, sleep is necessary for learning and memory. In practice, this means that when teenagers get enough sleep, they are more likely to perform better academically. Likewise, sleep is crucial for not only remembering information but also prioritizing it.  This prioritization results in better critical thinking and decision-making. Unfortunately, when teenagers don’t get the right amount of resting sleep, many different negative consequences ensue. 

In the long-term, the physical risks of not sleeping enough include:

  • Obesity: When we are tired and lacking energy, we tend to turn toward sweet and highly processed foods in order to get quick spurts of energy. Additionally, our bodies are less able to signal to our brains when we are full, resulting in us eating more. 
  • High blood pressure and risk of cardiovascular disease: Lack of sleep can increase our blood pressure and inflammation in our body over the long term, which are both risk factors for heart disease.
  • Weakened immunity: Our immune system is not as responsive when we are sleep-deprived, making us more vulnerable to infections. 
  • Poor balance and risk of accidents: Fatigue and lack of alertness can lead to unfortunate accidents such as falling, getting in a car crash, etc. 

When it comes to emotional health, studies have linked lack of sleep in teenagers to:

How can parents help their teenagers get better sleep? 

As a parent, it can be difficult to see your teenager struggle with sleep habits. Here are some tips you can try to help your student get better sleep:

  • No electronics in the bedroom: All electronics, whether they are phones, computers, or TVs emit blue light, which prevents adequate secretion of the sleep hormone melatonin. Instead of being on their phones, you could encourage your teenager to read a book or do another relaxing activity before bed. By removing electronics, you not only help them with sleep, but you also decrease the likelihood of exposure to suspicious websites alone in their rooms at night or them engaging in other risky digital behaviors, such as sexting.
  • Early Homework: Encouraging teens to do their homework earlier in the evening, preferably right after they come home from school promotes healthy sleep habits. This eliminates the need for procrastinated late-night study sessions. In addition, if they need to use the computer to do research or write an essay, working on it late is not optimal because of the impact of the computer’s blue light.
  • Melatonin supplements: Taking melatonin before bed can help induce sleep. However, studies have shown that people tend to take too much of it, which can result in harmful effects. The suggested amount should be between 0.5 and 5 milligrams. We recommend that you always seek the advice of a doctor before starting taking any supplement.

As we have seen, sleep affects teenagers’ physical and emotional health in profound ways. In this regard, at Pure Freedom, we promote healthy routines and habits, as well as digital boundaries with all of our students. 

If you want to learn more about supporting the young people in your life, subscribe to our monthly newsletter for blog and program updates. 

Written by Elodie Takamiya.


Jenson, Frences E. The Teenage Brain: A Neuroscientist’s Survival Guide to Raising Adolescents and Young Adults. Harper Paperbacks, 2016.