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Sign UpLight is one of the most powerful tools for adjusting your body clock. Logan Pendergrast, Ph.D., explains how to use and avoid light at the right times to support your sleep-wake rhythm when working nights or living on a flipped schedule.
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light is important because light is the
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most essential regulator of our body's
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circadian rhythms and the way that this
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works is is light from the outside
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environment let's say the sun for
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instance is perceived by the retinas in
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our eyes and that information is then
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relayed via a nerve to the brain
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specifically the superismatic nucleus
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which then tells the hypothalamus
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another region of our brain that
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releases hormones what time of day it is
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and this release of hormones from the
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hypothalamus then communicates this
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information to the rest of the body now
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exposure to light in the early part of
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our waking time is not just important
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for our general feelings of energy but
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it's also important for the next time
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that we go to sleep and this has been
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shown in individuals who are shift
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workers where shift workers who are
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exposed to artificial or natural forms
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of light upon waking show a 30%
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reduction in the disturbances of sleep
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the next time that they choose to go to
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sleep and so it's not just the case that
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light is helping us feel awake it's also
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the case that exposure to light early
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upon waking is helping us sleep the next
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time that we go to sleep now on the flip
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side of this coin it's also the case
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that exposure to light too close to
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going to sleep can influence our ability
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to sleep and the reason that this
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happens is this artificial light let's
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say from our screens or from our
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televisions is perceived by the eyes and
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the superismatic nucleus as being
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daytime and what this causes is a
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reduction in the release of a hormone
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called melatonin which is responsible
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for a drop in body temperature and a
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general preparedness for sleep and this
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reduction in melatonin will make us feel
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less sleepy and as a result can
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influence our ability to fall asleep so
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it's quite important to manage our
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exposure to light for our general
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circadian rhythms and our well-being
