We hear a lot about sleep, but sleep is only one piece of a much bigger story.
Inside each of us is an amazing biological timekeeper called the circadian rhythm. It helps coordinate many of the body's daily processes -- from sleep and wakefulness to hormones, body temperature, digestion, metabolism and energy.
And, this clock is designed to take its cues from the world around us.
Your body has a clock
Your circadian rhythm follows an approximately 24-hour cycle, with light and darkness being two of its most important signals.
Morning light tells your body that the day has begun. As daylight changes throughout the day and eventually fades into darkness, your biology responds accordingly.
This is why going outside in the morning can be so powerful. You are signaling to your body that it is daytime. And you don't need a special device or complicated routine.
The sun is the original biological clock.
Our modern lives have made it remarkably easy to erase the distinction between day and night.
We can turn on bright lights at midnight. We can scroll through our phones in bed. We can work late into the evening and sleep in the next morning.
Our bodies, however, haven't changed nearly as quickly as our technology has.
As evening approaches, our biology naturally begins preparing for rest. Darkness supports the body's nighttime processes, including the release of melatonin, which helps regulate the sleep-wake cycle.
This is one reason I believe darkness is so, so crucial to our overall health.
When we talk about circadian rhythm, we often immediately think about sleep. But your biological clock is involved in much more.
Circadian timing influences:
- Sleep and wakefulness
- Hormone rhythms
- Body temperature
- Digestion and metabolism
- Energy and alertness
- Immune function
- Mood and mental well-being
Our bodies are constantly keeping time.
And the more consistent our daily rhythms are, the more clearly our internal clock can understand the signals we're giving it.
What about the Earth's magnetic field?
There is another part of our natural environment that is easy to overlook: the Earth's magnetic field.
Life evolved within the Earth's geomagnetic environment, and researchers continue to explore how geomagnetic signals may interact with biological systems.
We don't yet understand all of the implications, but I find it fascinating to remember that we are constantly immersed in the natural environment around us -- not just sunlight and darkness, but also the Earth's electromagnetic and magnetic environment.
It is another reminder that our biology doesn't exist separately from the Earth.
The good news is that supporting your biological clock doesn't have to be complicated.
Try beginning with a few simple things:
Get outside in the morning. Let natural daylight reach your eyes.
Spend time outdoors during the day. Our bodies benefit from experiencing the natural changes in light throughout the day.
Move during daylight hours. Walking, gardening or simply being active outside can help reinforce the distinction between day and night.
Let evening be different from daytime. As the sun goes down, begin dimming the lights and slowing the pace.
Reduce bright artificial light at night. Give your body a chance to recognize that nighttime has arrived.
Sleep in darkness. Y our body needs nighttime signals just as much as it needs daytime ones.
And, one of the most important thing is to be consistent. A regular rhythm of waking, eating, moving, resting and sleeping can provide valuable cues to your internal clock.
We don't have to be perfect
I don't believe in making health complicated or feeling guilty when life doesn't go according to plan.
It's about creating more opportunities for your biology to receive the signals it recognizes.
Morning light.
Daytime movement.
Evening darkness.
Restful sleep.
Time outdoors.
A rhythm that feels a little more connected to the natural world.
We have spent so much time trying to control our environment that perhaps one of the simplest things we can do for our health is to pay attention to it.
Our bodies have been keeping time for thousands of years.
Maybe it's time we started listening.
