Ask An Expert·2 min read

Why is Sunlight Important for Regulating Your Sleep Cycle?

Dear Expert,

Why is sunlight important for regulating your sleep cycle?

Dear Anonymous,

Exposure to light, especially sunlight, helps synchronize the body's master clock, which controls the timing of many bodily processes, including your sleep-wake cycle. Without it, you might find it harder to fall asleep and stay asleep. Ideally, you should go outside within an hour of waking up. Light exposure in the morning signals that it's daytime and triggers the brain to…

  • Curb production of melatonin, a hormone that regulates the sleep-wake cycle

  • Encourage the release of cortisol, a hormone that promotes alertness 

It's important to take in light through the eyes (without wearing sunglasses), but don't look directly at the sun. If you can't step outside, keep your room brightly lit throughout the day. Then, on the flip side, you’ll want to reduce light exposure in the evening. You can do that by dimming your lights about two hours before bed.

Featured Expert

Dr. Nishi Bhopal

Dr. Nishi Bhopal - Board-certified psychiatrist and sleep specialist, and founder of IntraBalance and Pacific Integrative Psychiatry.

Ask an Expert is for informational purposes only, does not constitute medical advice, and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician, mental-health professional, or other qualified health provider with any questions you may have regarding a medical condition. By submitting a question, you are agreeing to let theSkimm use it—in part or in full—and we may edit its answer for length and/or clarity.

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