If the clock on the wall is telling you it’s time for bed, but you still feel wide awake, you might need to reset your circadian rhythm.
Your circadian rhythm is the internal clock that regulates your sleep/wake cycle. Michelle Drerup, PsyD, director of behavioral sleep medicine at the Cleveland Clinic, likens it to a 24-hour internal clock running in the background of your brain that cycles between sleepiness and alertness. When your circadian rhythm is misaligned, it can cause sleep issues, among other things.
Two possible disorders, according to Dr. Muhammad Najjar, assistant professor of medicine at the University of Illinois Chicago, are delayed sleep phase disorder and advanced sleep phase disorder, which are experienced by night owls and early birds who struggle to maintain a normal sleep schedule.
These disorders are associated with higher risks of mental health issues and attention deficit hyperactivity disorder, according to 2018 research. A separate study found a higher risk of cardiovascular disease linked to circadian disruptions. Najjar also cites daytime sleepiness, slower reaction times and decreased memory and concentration as possible side effects.
In most cases, Najjar notes, it’s behavioral factors such as traveling across time zones or working the night shift that are responsible for shifting your internal clock, not actual circadian rhythm disorders. Regardless of the cause, he adds, “If you are awake when you should be asleep, the system is less effective.”
You might not be able to ditch the night shift or want to give up international travel but there are ways to reset your circadian rhythm to improve your sleep (and your health) when necessary.
If the sun is shining when you need to be sleeping, do your best to minimize your exposure to light. “Wear dark sunglasses when you leave work in the morning [after a night shift],” Najjar says. Close the blinds to block out the sun before going to bed.
Scrolling through social media or watching TV in bed can wreak havoc on your internal clock. Research published in Cell Reports found the blue light from our screens disrupts circadian rhythm — and all it takes is 10 minutes of exposure.
“[B]right lights at night can disrupt your rhythm by confusing your brain into thinking it’s still daytime,” explains Drerup. “Artificial blue light — the type that laptops, cellphones and tablets give off — is often very disruptive, so trying to decrease light exposure and putting your technology to sleep an hour or two before bedtime can be beneficial.”
Up to 87% of people have bedtimes that differ between weekdays and weekends, according to one study. The shifts in sleep/wake times, known as social jetlag, not only interfere with your body clock, but they are also associated with obesity and cardiometabolic disease risk factors such as insulin resistance. Drerup notes that resetting your circadian rhythm requires going to bed and waking up at the same time every day, including weekends,
The best option for disorders like delayed sleep phase disorder and advanced sleep phase disorder is a general adjustment of your sleep/wake times. Instead of going to bed at 4 a.m. and sleeping until noon, shift to a 3 a.m. bedtime and 11 a.m. wake time and, over time, continue shifting an hour earlier until you are regularly going to bed and waking up during traditional hours. “You must maintain the schedule, [or] you’ll drift back into delayed patterns and have to repeat the cycle,” Najjar says.
If your body needs help shifting into sleep mode, consider taking melatonin. The hormone, which naturally increases at night to induce sleepiness, can also be taken (in supplement form) during the daytime to help you slip into slumber. Najjar recommends taking melatonin two hours before you want to go to bed to give it time to take effect.
When your circadian rhythm is out of whack, your sleep suffers but practicing healthy sleep habits helps get your internal clock back on track, resulting in longer, higher quality sleep.