There was probably a time in your young adult life when you could function on a disturbingly small amount of sleep. Maybe you used to pull all-nighters doing homework, then go to school without blinking an eye. Perhaps you used to stay out into the wee hours partying on week nights. Or, maybe you never even worried about getting enough sleep, because you had so much energy. But as you grow up, you may feel like you've regressed into a little baby who needs hours of nap time and rigid bedtimes in order to function. So, what gives?
As we grow, our sleep cycle changes, Raj Dasgupta, MD, FAASM, assistant professor of clinical medicine at Keck School of Medicine at the University of Southern California, told Refinery29 in an interview last month about baby sleep trends. Most adults need 7-8 hours of sleep a night, whereas teens need 8-10 hours, kids need 9-11 hours, and toddlers need about 11 to 12 hours. "[A kid's] sleep cycle is different, so they move through different stages of sleep compared to adults," he said. In other words, while the actual amount of sleep you need doesn't change that much as you age, your sleep "architecture" or pattern does.
If you've never heard of "sleep architecture," here's how it works: Throughout the night, your body cycles through a pattern of rapid eye movement (REM) and non-rapid eye movement (NREM) sleep periods, which last for about 90 minutes in adults. Then, there's something called "slow-wave" deep sleep, which is supposed to be the "restorative" stage of sleep that generally lasts 20-40 minutes and doesn't involve dreaming. When you enter early adulthood (age 16-25), the amount of slow-wave sleep begins to decline, according to the Division of Sleep Medicine at Harvard Medical School. From there, it gets worse, and elderly adults have even fewer, shorter periods of slow-wave sleep. So, young adults tend to have better, longer sleep than older ones, according to the Mayo Clinic.
All of this is to say that your sleep quality is just not what it used to be when you were a kid or even a teen. In fact, some experts say that "late childhood is the golden age of sleep." But besides age, there are a few other factors that can contribute to poorer sleep. For example, if you're pregnant, then changes in your body can result in worse sleep, according to the Mayo Clinic. You may also have developed a caffeine habit in your adult years, which can also interfere with your ability to fall asleep. And, if you find yourself glued to your phone or other screens before bed, then that's another reason why it's harder to find some shut eye.
Sure, it may sound pessimistic that the "golden age" of sleep is in your past, but just consider this another reason why you should really take your sleep hygiene seriously. That means, setting consistent bedtimes, limiting daytime naps, avoiding caffeine around bedtime, and setting up your bedroom environment for good sleep. Who knows? Maybe these simple tweaks will help you sleep like a baby — or at least a younger you.