Can a One-Hour Time Shift Disrupt Your Circadian Rhythm?

Every November most of us turn back the clock by an hour as daylight savings time comes to an end. But other than the extra hour of sleep that night and the darker winter days that follow, do we understand how this seemingly small change affects us in the grand scheme of things?

Originally established as a policy to conserve energy, the practice was intended to grant us more daylight in the summer so that artificial lighting could be used to a lesser extent. Most recently, however, energy conservation has been reported as highly marginal, while an expansive web of negative health effects has been linked to the time changes from daylight savings. The 1-hour shift in March and again in November actually affects everything from our mood, to our cognitive function, to our physiological health.

The Biological Effects from Switching In and Out of Daylight Savings Time

Seasonal Affective Disorder (SAD), also known as seasonal depression, for example, is described by the National Institute of Mental Health as a type of depression that comes and goes with the seasons–typically starting in the late fall and early winter and fading off during the spring and summer. The reduced exposure to sunlight during this time may affect levels of the neurotransmitter serotonin, which plays a role in mood. Links have been found between lower levels of serotonin and depression.

Additionally, more time without the sun may cause an increase in the sleep-related hormone melatonin, which is naturally produced by the body when we are in dark environments. The shorter, darker winter days may lead to an increase in melatonin production for some people, which would cause them to feel more lethargic. Abnormal levels of melatonin can also throw our biological clock–known as the circadian rhythm–out of sync with the usual sleep/wake rhythms. This is a fundamental problem as the disruption of the natural circadian rhythm can lead to a slew of harmful effects on the body.

When it comes to daylight savings time in March, which causes us to skip ahead and lose an hour in return for more daylight, research has found an increased risk in stroke, heart attacks, and even traffic accidents in the days that immediately follow the time shift.

It is no coincidence that these adverse events typically come with sleep loss. As Associate Professor of management at the University of Washington Christopher Barnes explains,

“When we change the time by one hour, it throws a monkey wrench into our circadian process…The following Monday, we’ve discovered that people have about 40 minutes less sleep. Because we’re already short on sleep to begin with, the effects of even 40 minutes are noticeable.”

And according to a recent review of the literature published in European Review for Medical and Pharmacological Sciences, “Transitions into and out of Daylight-Saving Time (DST) may disrupt circadian rhythms and lead to sleep disturbance and deprivation.”

Circadian Lighting as A Solution

Since many of the harmful effects from daylight savings time are linked to the disruption of the circadian rhythm, having the proper biological light can help prevent or reverse these effects by regulating our circadian clock properly. Bios SkyBlue™ lighting technology is spectrally-optimized to mimic natural sunlight. By utilizing the ipRGC photoreceptor in the eye, SkyBlue™ lighting technology produces the natural blue sky light wavelength necessary to communicate directly with our circadian biology and help regulate sleep, along with many of the body’s physiological processes. Implementing SkyBlue™ technology into office lighting can help people regulate circadian rhythm — and help mitigate the issues caused by moving the clocks.

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