Circadian Rhythms: How to Light Your Way to Better Sleep

We are creatures of the light, and light affects us in more ways than we might realize.

Beyond the simple dichotomy of light and dark, various wavelengths of light send drastically different signals to our bodies and brains. These signals make (or break) our circadian rhythm.

We already know that disrupted circadian rhythms can cause anxiety and increase inflammation. The reverse is also true: Proper signaling and a well-tuned circadian rhythm are foundational to quality sleep and good health.

What Is a Circadian Rhythm?

Simply put, the circadian rhythm is the cycle that our body goes through in a 24-hour period.

On a very basic level, light signals wakefulness and darkness signals that it’s time for sleep. But the reality of the human body’s response to light is infinitely more complex.

The two primary circadian hormones are cortisol and melatonin.

Cortisol is vital to a regulated metabolism, memory formation, and other key processes. Melatonin helps to regulate our sleep-wake patterns and plays a crucial role in the repair that happens while we sleep.

Ideally, your cortisol rises gradually each morning and then declines so that you’re ready to sleep at night. Melatonin production peaks in the middle of the night while you sleep.

These master hormones influence other vital hormones that are produced on a 24-hour cycle such as insulin, leptin, and ghrelin.

So, what can we do to support a healthy circadian rhythm?

A Good Night’s Sleep Starts at Dawn

Start your day right by watching the sunrise. It doesn’t have to be a big production: Simply looking east for a few minutes while the sun is still within ten degrees of the horizon can send your brain the signals that it needs to stop producing melatonin and slowly increase cortisol.

It’s okay if you don’t have an unobstructed view of the horizon. Even with clouds or buildings in the way, you’ll get the light signal you need. Looking through an open window works too—but ideally not through glass.

After that, spend as much time outside as you can. Remember, the whole idea is to let the light in! Unless you’re in an extreme environment like a sailboat or the slopes, ditch the sunglasses.

Rising with the sun and witnessing that early morning UVA light can transform your health in myriad ways. Try it for a few days and see what shifts for you.

Support Your Circadian Rhythm with Food

So, you woke up early and gazed east for a few minutes at sunrise. Fantastic! Now what?

Once you’ve rehydrated with some water, make yourself some breakfast.

Sarah Kleiner, a Quantum Health Coach and Certified Nutrition Coach, advises eating a breakfast that contains protein and fat about half an hour after sunrise. Caffeine, if consumed at all, should wait until after.

Eating within one hour of sunrise helps to balance blood sugar and moderate cortisol production. It also signals your body to wake naturally around the same time the next day—so every day that you rise with the sun and eat a balanced breakfast soon after, those early mornings will feel easier.

These early breakfasts will also improve leptin signaling, helping you develop more reliable hunger signals over time.

Whole foods from local farmers are a great choice for any number of reasons, including light signaling. When those of us outside of warmer climes eat tropical fruit in the dead of winter, the signals we’re sending our body can get hopelessly crossed. Eating local foods in season is ideal.

Experts recommend eating dinner before dark, ideally three to four hours before bed. If you’re hungry at bedtime, Kleiner recommends a small snack, like a spoonful of healthy fat.

Wintertime Adjustments for the Circadian Rhythm

People often fret about adequate sun exposure in wintertime. While it’s good to soak up all the sunny days that you can, winter can provide a wonderful opportunity to reset.

The sun rises later in the winter, for one thing. Get into the habit of catching the sunrise while the days are short—even if it’s just through a cracked window—and it will be easy to wake up a few minutes earlier each day when the days grow longer again.

Temperature also sends signals to the body. Cold exposure in the morning (walking outside, taking a cold shower, or dunking your face in ice water) and a warm bath before bed each help regulate your circadian rhythm.

Winter is prime time for sleep and repair. Use those long nights to rest and heal.

What About Red Light Therapy?

Red light has the potential to boost melatonin production and improve sleep. Red light devices can be a wonderful way to increase your exposure to these healing wavelengths.

Circadian biology expert Carrie Bennett advocates for a moderate approach to red light therapy because too much isn’t necessarily beneficial. She recommends using red lights for 10 minutes at a time, about six to eight inches away from each part of your body that your light covers.

Experts recommend limiting your exposure to red light to the hours between sunrise and sunset due to the brightness.

Decrease Blue Light for Better Sleep

When we inundate our brains with blue wavelength light (think white bulbs and the screens of our devices), our brains are getting the signal that it’s noon on a summer day. All. The. Time.

With that sort of signaling, it’s no wonder we have trouble settling into restorative sleep.

Cortisol is wonderful and necessary, and so is blue light. But when we continuously spike our cortisol at all hours by staring at our phones or keeping our houses bright as day right up until it’s time for bed … well, things can spiral out of control.

Luckily, there are many ways to decrease your exposure to blue light.

One simple way is by wearing a high-quality pair of “blue blockers” whenever you’re exposed to artificial light. These rose-colored lenses (okay, so they’re more likely to be red or yellow) block blue wavelengths of light and only allow non-disruptive colors to pass through.

If you’d rather not wear glasses, there are other easy workarounds. You can buy inexpensive lightbulbs that don’t produce blue light. Some are red, while others have a soothing golden glow. Use them in place of standard white bulbs.

Consider setting your phone and computer to night shift all the time; it’s easier on your eyes. At the very least, they should be set to night shift after dark.

In a perfect world, we wouldn’t be staring into artificial lights after dark at all. If you have to be on a screen after sunset or before sunrise, consider shifting it all the way to red. You can search for tutorials online that take you through the steps for your particular device. I was able to change the settings on my phone so that the screen shifts to red with a triple-click of the side button. I use this if I’m reading after dark.

Once your devices are set towards the warmer end of the spectrum, you’ll realize how harsh and disruptive the blue light from screens really is.

Bringing It All Together

Don’t let perfect be the enemy of good. Taken all together, this list might seem overwhelming. But if you just choose one thing—stepping outside at sunrise, wearing blue blockers, or whatever else mentioned that feels most accessible to you—and slowly ramp up, you’ll find that each of these things actually makes your life less stressful.

Throw open the windows. Step outside for a few minutes whenever you can.

Invite more sunshine into your life.

Meditation can help with seasonal affective disorder—learn how.