Darkness causes the release of the hormone melatonin, which is a highly effective all-natural sleep aid. Even a small amount of light can throw off your melatonin levels, and it takes only a few minutes for this to happen. Dim the lights about 30 minutes before bed, and turn off all electronic devices, including smart phones, computers and iPads. Block outside light from the moon and streetlamps with opaque blinds or curtains. Night-lights with red bulbs have less of an effect on melatonin than white ones, and alarm clocks with red numbers are less disruptive than ones with white or blue digits.
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