Can a Circadian Rhythm Be Changed?
Do you ever notice that you tend to feel energized and drowsy around the same times every day? Maybe you’ve thought that’s from the coffee you had (or didn’t have!) that morning. Or you ate a big lunch and that made you sleepy. Sure, that does impact your level of wakefullness. But there’s a bigger, biological factor at play: Your circadian rhythm.
What is the circadian rhythm?
Your circadian rhythm is a 24-hour internal clock that is running in the background of your brain. It’s what cycles you between sleepiness and alertness at regular intervals. It’s also known as your sleep/wake cycle. But it also goes beyond just sleep (because sleep is so connected to everything else in your body.)
Your circadian rhythm also effects your overall health, too. It impacts the cycle of hormone release, eating habits, digestion and even body temperature. It’s often connected to sleep, though, because that relationship is more obvious to us day to day.
What impacts the circadian rhythm?
At its essence, this cycle is based on light and dark (or day and night). That being said, it is a complete biological and natural thing that happens with us normally as humans. It may be impacted by external factors, but it’s established in us naturally.
A part of your hypothalamus controls your circadian rhythm. When it’s dark at night, your eyes send a signal to the hypothalamus that it’s time to feel tired. Your brain, in turn, sends a signal to your body to release melatonin, which makes your body tired. That’s why your circadian rhythm tends to coincide with the cycle of daytime and nighttime.
It can be thrown off kilter, however, by working shift work, when travelling and experiencing jet lag that interrupts our normal light-dark cycle and exposure to blue light from electronics.
The daily highs and lows
For most adults, the biggest dip in energy happens in the middle of the night (somewhere between 2:00am and 4:00am, when they’re usually fast asleep) and just after lunchtime (around 1:00pm to 3:00pm, when they tend to crave a post-lunch nap). Those times can be different if you’re naturally a night owl or a morning person. You also won’t feel the dips and rises of your circadian rhythm as strongly if you’re all caught up on sleep.
This time between 2:00 - 4:00am is when you’ll normally experience your deepest levels of sleep. Deep sleep is the time our bodies heal and regenerate. Blood supply to your muscles and organs increase. This is the sleep stage for growth, development and overall health. So, being sound sleep to really enjoy this period of deep rest is important for adults to stay health and children to grow and develop. This is why getting to bed a good time to be sleeping soundly by 2:00am is super important.
Optimize your circadian rhythm for quality sleep
Your circadian rhythm works best when you have regular sleep habits, like going to bed at night and waking up in the morning around the same times from day to day (including weekends). When things get in the way, like jet lag, daylight savings time, or a compelling sporting event on TV that keeps you up into the wee hours of the morning, you can disrupt your circadian rhythm, which makes you feel out of sorts and can make it harder to pay attention.
Changing your circadian rhythm
So now that we know what a circadian rhythm is the question on a lot of people’s mind is, “Can I change my circadian rhythm?”
The short answer is yes - it shifts naturally but there is more you can do to help it. Whether you are an early riser or a night owl your circadian rhythms naturally change as you age. For example, the body clock shifts during adolescence, making teens want to go to bed later and sleep longer than younger kids. Your work or school schedule may mean that you need to switch from a night owl to an early bird. You can try to alter your circadian rhythm yourself, but do it slowly. For example, try waking up 15 minutes earlier each morning over the course of a week.
Other sleep tips
If you want to improve your sleep and take control of your rest, these guides can help you: