Balancing Light and Darkness for Better Sleep

It’s no secret that most people do not get enough sleep. What may be surprising though, is the effect light and darkness could be having on the sleep and wake patterns of you and your employees.

Our bodies use light and darkness to cue physiological processes in coordination with an internal 24 hour circadian rhythm system. Improper timing of light exposure and darkness can disrupt the signaling needed to activate neural systems and hormones that control basic biological functions such as energy balance, DNA repair, protein production, as well as sleep and body temperature. These disruptions can lead to chronic medical conditions including obesity, hypertension, diabetes, heart disease, depression, and even cancer.

In the morning, light from the sun, in the blue­green spectrum, activates wake systems in the brain and shuts off sleep. This is due to direct activation of the master switch for circadian rhythms in a small brain region called the supra­chiasmatic nucleus, or SCN. Subsequently, multiple brain regions that drive wakefulness become active while simultaneously brain centers that promote sleep, such as the pineal gland where the hormone melatonin is produced, are inhibited.

During the day, as sunlight fades to darkness, body temperature drops, metabolism slows, and melatonin production begins. The increase in melatonin helps with the transition to sleep and as the night continues, so to does the production of melatonin in the brain.

This is how things are supposed to work, but in a world full of artificial light, many people’s circadian rhythms are disrupted.

After the sun goes down, if the brain receives artificial blue­green light—like that from tablets, mobile devices, and computers—it can be fooled into thinking it is still daytime. This lowers melatonin levels during the night, making it difficult to fall asleep. In addition, sleep deprived people also develop other hormonal imbalances such as an increase in the ratio of ghrelin:leptin, two “push­pull” hormones that regulate appetite, which drives eating behavior and ultimately weight gain and potentially diabetes.

The good news is that you can improve your sleep and wake patterns for better performance and overall health just by avoiding light at certain times and using it at others.

In the morning, try to get lots of bright natural light in order to accentuate your natural drive for mental and physical activity. As the day fades into night, power off as many light­emitting devices and if possible chose lower wavelength light sources such as red and/or yellow lights.

These have less effect on the nighttime transition. This includes a campfire, candlelight, and even an incandescent light bulb that is dimmer and redder than a new compact fluorescent lamp (CFL). Additionally, make sure you’re sleeping in complete darkness, and limit light if you have to get up in the middle of the night.

By being intentional about the type, amount, and timing of light allowed into your life, you can improve your sleep patterns and reduce your risk of disease. This means fewer health concerns, fewer sick days, and fewer delays in meeting your goals.

FusionHealth is the leader in providing technology enabled sleep health solutions for self-insured employers to deliver lasting results to their employees, their families and their companies.

*Reference:
http://www.ncbi.nlm.nih.gov/pubmed/15583226
http://www.ncbi.nlm.nih.gov/pubmed/19255424
http://rstb.royalsocietypublishing.org/content/370/1667/20140120
http://www.cdc.gov/features/dssleep/