Knowing how your body clock works may help you sleep better at night.
Have you noticed how you want to nap the same time each afternoon or how your eyes start to feel heavy in the evening around the same time? Maybe you wake up at the same time each morning, with or without an alarm. Perhaps you’ve experienced jet lag after flying across country and your body takes a few days to adjust. Or when your alarm goes off, it feels like the middle of the night. All these events are related to your body clock.
You know there’s not a ticking clock hiding in your body, so what exactly is your body clock and how does it work?
Each day, your body functions on a schedule. If it doesn’t, it wishes it did. Most living things (plants and animals included) have circadian rhythms controlled by their individual body clocks. Throughout the day you may notice mental, behavioral, or physical changes in your body. You feel sleepy, awake, or hungry at similar times each day. Running on a 24-hour cycle, your sleep-wake pattern, eating schedule, body temperature, hormone production, and digestion all function on a circadian rhythm.
This daily cycle is controlled by your body clock. Timing devices are special proteins that interact with cells found in every body tissue and organ. The master clock is located in the hypothalamus of the brain. Called the suprachiasmatic nucleus (SCN), this bundle of nerve cells receives information from the eyes and surrounding environment and sends signals to the timing devices throughout the body.
Daylight is the greatest influence on circadian rhythms, though your body will continue to function on a similar schedule if kept in darkness. Changes in the amount of light or darkness you’re exposed to and you’ll slow down, speed up, or reset your biological clock.
Knowing how your body clock works can help improve your quality of sleep. As the SCN receives information about light and darkness, it produces melatonin, a hormone that induces sleep. The less light, the more melatonin is released. Want a good night’s rest? Turn down the lights and turn off all screens an hour before bedtime. Have trouble waking up in the morning? Turn on the lights, open the blinds, and sit in the sunlight to signal your body to stop making melatonin and to wake up instead.
Routine Is Good
As you age, your body clock changes. Infants require up to 17 hours of sleep a day, young children need 9 to 11 hours, teenagers 8 to 10, and adults 7 to 9. Elderly folks, as is sometimes joked about, often begin waking up and needing to go to bed earlier. Teenagers often feel more awake later in the evening and want to sleep in. While this is normal, school schedules interfere, making many teens sleep deprived.
No matter how much sleep you need, your body craves routine. A consistent nap schedule for children helps them sleep better at night. If late nights have you begging to sleep in on Saturday, limit the extra sleep to an hour or two. Need a nap? Rest for less than 30 minutes if you want to wake up refreshed.
Going to bed and waking up the same time every day—weekends included—keeps your body clock ticking on time. A clock that’s thrown off not only affects your sleep but your hormones, immune system, and digestion as well. Studies reveal a link between out of sync body clocks and your risk of cancer, obesity, diabetes, and mental health conditions.
So get your clock on time and your body will be ready when you need it!