Whether you’re ready to go when the sun rises or energized late into the night, making sure you’re getting adequate sleep is essential for a healthy lifestyle. And one of the keys to feeling more refreshed may just lie in accepting that you have a natural sleep/wake pattern, also known as your chronotype.
“The same way the heart has a pacemaker, the sleep process has a pacemaker — your sleep rhythm,” says Dr. Ana Krieger, director of the Center for Sleep Medicine at NewYork-Presbyterian/Weill Cornell Medical Center and Weill Cornell Medicine. “It’s important to understand your sleep cycle so you can adjust your life to your chronotype and figure out what you can do to improve your sleep.”
Health Matters spoke with Dr. Krieger, who is also chief of the Division of Sleep Neurology and a professor of clinical medicine at Weill Cornell Medicine, to learn more about how to protect and improve the quality of your sleep, no matter what your personal sleep cycle looks like.
Why are some people early birds while others are night owls?
Dr. Krieger: Chronotypes, like being an early bird or a night owl, relate to our genetic inclination to sleep at a certain time of the day. We have genes that regulate our sleep cycles and release melatonin at a particular time to help prepare for sleep. This is a complex process that also involves the synchronization of other metabolic processes and hormones, including growth hormones and cortisol, and decreases your body temperature.
For night owls, all of that happens later. So, when people force themselves to go to bed early, they might be unable to sleep simply because the body isn’t ready.
People who go to sleep before 9 p.m. have what we call advanced sleep phase. Others who go to bed after 2 a.m. have what’s called delayed sleep phase. Only a small percentage of the population will be on those two ends: around 4% have delayed sleep phase and 2% or less have advanced sleep phase. Most people usually fall on a spectrum between the two, sleeping between 9 p.m. and midnight.
Being an early bird or night owl may not be a definite diagnosis for some people, as we may identify with different chronotypes at different times in our lives.
There are also behavioral aspects that can create a self-imposed sleep restriction. Work demands, school schedule, or environmental pressures may affect a person’s ability to self-regulate. If someone only gets five or six hours of sleep per night during the week because of their work schedule, they may wake up later on the weekends and perceive that they are a night owl. But that may not be their natural pattern, they could just be catching up with sleep.