Blue Light Blues

In today’s society, it is getting more difficult to shut off our devices and get some “shut-eye.”

Studies from Harvard medical school have shown that even partial sleep deprivation can affect our mood and even mood disorders.

As you use your cell phone throughout the day, a particular part of our eyes is used to sense light.

The retina towards the back of the eyeball has several different light receptors.

Rods are used for night vision but do not see color.

Three kinds of cones sense different wavelengths of light: red, blue, and green.

The last receptor in your retina tells the brain whether it is light or dark outside.

According to an article by Psych Education, “this certain light and dark receptor is tuned to sense only blue light.”

The light and dark sensors connect with your internal clock rather than your vision center.

On a spectrum of sunlight and its intensity to the eye, a blue light shows up as a shorter wavelength.

Another effect that blue light has on our body is to our circadian rhythm.

The National Institute for General Medical Sciences describes the circadian rhythm as “physical, mental, and behavioral changes that follow a daily cycle. They respond primarily to light and darkness in an organism’s environment.”

This rhythm synchronizes specific processes through a daily cycle partially regulated by sunlight.

Some of these regulated processes include sleep and wake behavior.

According to Mental Health America, “increasing evidence shows their [processes] disruption can lead to certain cancers, metabolic dysfunction, and mood disorders.”

The American Academy of Pediatrics did a study in 2016 and found that there has been a 37% increase in reported mood disorder symptoms among young people over a nine-year period.

When one of our three light receptors directly responds to light, the response reaches specific brain regions that then affect our emotions.

For example, think about how sunny days may make you feel happier than a cloudy day.

Blue light is naturally emitted from sunlight and the intensity of the wavelengths changes at different times of the day.

When the sun sets, it should, therefore, limit our exposure to blue light; however,

electronic devices have prolonged our exposure.

The strongest wavelengths tend to come from artificial lighting emitting from electronic devices.

When the brain regions are disrupted, it can also damage the brain’s ability to deliver melatonin which can then lead to mood disorders.

Mental Health America says, “Melatonin is a hormone that peaks at night to help us get a restful night’s sleep and regulates the circadian sleep phase.”

Sleep disruption can then lead to mood disorders such as depression, bipolar disorder, and anxiety.

You may be asking yourself, what can I do to limit blue light at night time resulting in better sleep and lowering risks of mood disorders?

The easiest way is to limit screen time.

Dr. Abdul-Hadir Hourani M.D., a sleep medicine specialist suggests to shut off electronic devices two hours before bedtime.

Blue light blocking glasses also help by blocking a portion of blue light wavelengths from hitting your eyes.

These glasses are even useful for other blue light emitters such as fluorescent lighting in buildings and from headlights while driving at night.

Many cell phones and computers now also offer a night shift setting which radiates a yellow tone, taking out the blue light, and making it more comfortable on the eye.