The circadian rhythm that helps our bodies establish a regular sleeping pattern is heavily influenced by sunlight and darkness. The morning light is a cue for us to wake up, but people can't always rise with the sun in wintertime, on cloudy days, or in rooms with few windows. If you can't get the real thing, a sunrise alarm clock is a great alternative. Program the time you'd like to wake up, and the built-in light will gradually become brighter in the minutes before the alarm sounds. Available on Amazon; $33.99.
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