Elemental explains why early sunshine is a cure-all.

Kelly Glazer Baron, PhD, director of the behavioral sleep medicine training program at the University of Utah, says if people don’t get the right cues for wakefulness, the body will feel out of sync. The body’s circadian rhythm — basically, its internal clock — is naturally a little longer than 24 hours. That means many of the bodies’ processes, like sleep, hormones, mood, and appetite, naturally rise and fall over a 24.1-hour timespan. Exposure to morning light is one way to lock the body into a 24-hour schedule the entire world runs on, which means better sleep at night and more alert, energetic mornings.

“When those rhythms are off, you might have trouble getting out of bed in the morning and then have trouble falling asleep at night,” she says. “That happens to a lot of us on the weekends when we stay out late, then sleep in and miss the morning light exposure — then, when bedtime comes, we’re not sleepy.”

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