Parenting Advice:
Is Sleep the Most Important Happiness Habit?

Christine Carter, PhD

January 28, 2010 06:04 PM

If I posted a video of my daughter when she is sleep-deprived and trying to finish her homework or clean her room—or do anything, really, that she doesn't want to do—I would lose all credibility as a parenting expert. This is because you would all witness her shockingly bad behavior, from bratty-voice screaming to head-on-the-desk, teary, fist pounding protests.

We humans don't really function all that well when we are seriously tired, and that is especially true for little humans whose brains are not yet fully developed. As Arianna Huffington writes in this post, sleep might just be the key to our happiness and peak performance.

Nothing could be more true for children.

Kids need a lot of sleep to be happy. Unfortunately, studies show that kids are getting significantly less sleep per night than they did in previous generations. This is of no small consequence.

Sleep deprivation—or just getting slightly less sleep than they need—affects kids' functioning and well-being in a huge range of ways. Not getting enough sleep can make kids:

  1. Less smart. In one study, researchers restricted the sleep of some students and extended the sleep of others for about 40 minutes over just three days. Kids who got less sleep showed worse performance in areas like learning, memory, and reaction times. How much worse? The difference between the two groups was "larger than or similar to the highly significant age differences between the fourth and sixth grade students" in the study. Losing two hours of sleep over three days set kids back two years.
  2. Inattentive. Sleepiness makes it hard for kids to pay attention, whether to their school work or to their parents. The effect of not getting enough sleep is much more evident in younger children, who tend to be quite distractible when tired.
  3. Fat. Sleep affects dozens of physiological and hormonal processes throughout our bodies, like how we store fat and burn calories. Kids who are "short sleepers" are more likely not just to be fat, but to actually be obese.
  4. Less creative. Sleep helps kids with verbal flexibility so that their speech is more articulate and creative. Decreased sleep can make them less fluent, and it can impair their thinking in ways that make them less imaginative and less able to problem solve.
  5. Moody and ill-behaved. I think this is obvious to every parent of every child who has ever missed a nap, but loads of good research backs this up: not getting enough sleep can make five year olds act like three year olds—miserable three year olds, to boot. Substance use, including using caffeine, alcohol, and tobacco, is greater in teens who sleep less, indicating that they are trying to cope with how they feel when tired.
Bad behavior often comes from the fact that sleepiness makes it hard for kids to control their impulses. Given my interest in Raising Happiness , I think this is the most important consequence that not getting my kids into bed on time can have. Why be awake if we are likely to be crabby and unhappy until we get more sleep?

In future posts, I'll dig a little deeper into the sleep research in order to give parents some good guidelines about sleep and their children's happiness. I'll address questions such as: How much sleep do kids need at different ages? Does messing up weekend sleep matter—can we let our kids stay up late once or twice a week without suffering the consequences? Can students make up for lost sleep on the weekends? What does research show we can do to help our kids fall asleep faster and to sleep better?

If we parents have taken the sleep challenge ourselves, the research makes it clear that we ALSO need to take it for our children. Helping our kids get more sleep can have tremendous, positive effects. Because of this, I have recently moved my kids' bedtime to a shockingly-early 7:30 pm (they are 7 and 9 years old, and they catch the bus at 7:50 in the morning). This means that I am trading quality bonding time with my children for sleep. But, given the profound effects sleep has on their health and happiness, I don't think I have a choice: ensuring that my kids get enough sleep is my responsibility as a parent.

Selfishly, I'm also hopeful that when my kids get more sleep, and their moods and behavior improve as a result, our time together will be more positive.

Will it work? Although the one-month Huffington Post sleep challenge is coming to a close, there is still time to take a sleep challenge for your kids. Research shows that it only takes 3 days of increased sleep to significantly influence your children's intelligence and mood for the better. Are you ready?

Christine Carter, Ph.D., is a sociologist and happiness expert at UC Berkeley's Greater Good Science Center, an interdisciplinary research unit that studies the psychology, sociology and neuroscience of well-being, and teaches skills for a thriving, resilient and compassionate society. Best known for her science-based parenting advice, Dr. Carter follows the scientific literature to understand ways that we can teach children skills for happiness, emotional intelligence, and resilience. She is the author of the new book Raising Happiness: 10 Simple Steps for More Joyful Kids and Happier Parents. Dr. Carter has a private consulting practice helping families and schools structure children's lives for happiness, and she lives near San Francisco with her family.


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