If you ask clinical psychologist Michael Breus, PhD, also known as The Sleep Doctor, his number one tip for having more energy and sleeping better, he doesn’t hesitate to share his own morning routine: He gets up at 6:15 a.m. every day , drink a large glass of water and meditate while waiting for the sun to rise. Then, at 7 am sharp, he walks his two dogs, Hugo and Moose, around the block, making sure to leave his sunglasses at home.

“Every human being, as soon as possible after waking up, should go outside and receive at least 15 minutes of direct natural light. Period,” says Breus, a Los Angeles-based sleep medicine specialist and co-author of the new book. Energize!Go from dragging your ass to kicking it in 30 days.

Breus’ simple life hack reflects a growing body of scientific evidence linking ample exposure to bright light early in the day with everything from sleeping better and thinking more clearly to better mental health and a lower risk of obesity and diabetes. .

“Light is the most important element in setting our circadian clock, or internal 24-hour rhythm, and morning light is key,” says Nathaniel Watson, MD, a sleep specialist and professor of neurology at the School of Medicine. the University of Washington.

Each of us has not only a master clock deep in our brain, but also a series of other clocks within our tissues that control when hormones are released, maintaining our sleep-wake cycle, hunger patterns, and other rhythms. daily working in a predictable manner. cycle.

If you lived in a cave with no light at all, the hands of the master clock would still click, but on a cycle of approximately 24.2 hours, slightly out of sync with the clock that society operates by. Every day, you would become more out of sync.

“Today, your clock would say it’s 7 a.m., but your biological clock might say it’s 6:50 a.m.,” says Mariana Figueiro, PhD, director of the Light and Health Research Center at the Icahn School of Medicine in New York. York. “Tomorrow, your biological clock could say it’s 6:40 am, and the next day it’s 6:30 am and it would be increasingly difficult to get up.”

Open the blinds or go outside, and the instant the morning light hits your eyes, you’ll synchronize your body clock with the 24-hour day in two critical ways:

• Specialized cells in the retina tell the brain to stop producing melatonin, the sleep hormone.
• Your brain’s master clock sets a sort of internal stopwatch, telling the body to start producing melatonin again about 14 hours later.

Morning light also pushes the body to increase the production of the stimulating hormone. cortisolactivating your brain for the day.

In one experiment, office workers got more morning light for 5 days. They found it easier to make decisions and scored 79% higher on cognitive tests.

Studies Show Morning Light Can Also Affect Hormones leptin (the satiety hormone) and ghrelin (the hunger hormone) so that they promote a healthy body weight.

And researchers at Northwestern University found that people who were exposed to the most bright light before noon weighed slightly less (1.4 pounds, on average) than those who were exposed to the brightest light at night. .

On the other hand, it is best to minimize bright light at night, as it has the same wake-up effect as in the morning.

“Light is like a cup of coffee,” says Figueiro. “It has a direct and acute effect and that is to maintain alertness, and that happens day or night.”

Bright, short-wavelength light or “blue light” (the bright screen of your laptop or smartphone) is particularly disruptive to sleep, as it more closely mimics the natural sunlight we evolved to wake up with.

Do your best to spend a minimum of 1 hour outdoors each day.. That includes at least 15 to 30 minutes in the morning after sunrise. Another good time to walk outdoors is between 1 and 3 p.m., when the body produces another brief surge of melatonin.

“Instead of grabbing coffee when you start to feel sluggish in the afternoon, go outside and take a sun break,” says Breus. Leave your sunglasses on to get the full effect.

In front of a window. If you spend most of your time indoors during the day, face the window and open the blinds whenever possible.

If your day room has no window, or only a small one, add more light. Figueiro recommends a table lamp on either side of his computer (1,500 lumens each) with a light-colored shade that diffuses light. A white bulb will suffice, but for greater effect, opt for a blue light or place the light closer to your eye.

Get an extra boost. If you drive to work in the dark, travel across time zones frequently, or have trouble getting natural morning light, using a “sunrise simulator” or “light therapy” lamp in the morning can also help. , says Watson: They can give you a whopping 10,000 lux of bright light. That’s about five times the brightness of outside light on a very cloudy day.

Set a curfew for screens. To minimize light at night, turn off your electronic devices (or at least dim the screen and set it so that words appear in white on black) 2 hours before bed. If you really have trouble relaxing, consider wearing blue light-blocking glasses 90 minutes before bed. Also use warm, soft, low-level lighting in your bedroom and living room at night.

And yes, you also need to maintain a consistent schedule: going to bed at the same time every night and getting up at the same time every day. It’s simple, but not easy.

“Sleep is nourished by consistency and routine.” says Breus. As a sleep coach for celebrities and athletes in Los Angeles, he knows how difficult it can be. But, as he himself says, if you want to sleep better, it’s worth it.