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Set the mood for slumber

Keeping your room dark while you sleep is a great start, but bringing the lights down before bed is also important. “Bright light too close to bedtime can make it hard to fall asleep,” Arnedt says. That’s because dimness signals the biological clock that it’s time to wind down, while bright light says “daytime!” Swap out überbright bedroom bulbs for low-watt ones, or install a dimmer switch and keep it low. Like to read in bed? Do it in the lowest light that’s still comfortable.

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