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Waking up at a consistent time can help keep these body functions running smoothly, said Helen Burgess, the co-director of the Sleep and Circadian Research Laboratory at the University of Michigan.
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There’s no specific amount of time you must spend in the morning sunlight, experts said, but, more exposure is better (as long as you protect your skin). Dr. Burgess said an hour is best, but even 15 minutes is better than nothing.
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