Sleeping with the Light On – Does It Matter?

Sleep Tips

With longer days and later sunsets,  light can spill over into the hours usually reserved for sleep. Add to that the temptation to keep all kinds of electronic devices that emit light in our bedrooms, from iPads to TVs to cell phones, and you have a perfect storm of several sources of light entering the room where we rest. Let’s talk about how light affects our sleep and what we can do about it.

Does Light Affect Your Sleep?

Light is indeed one of the most critical factors affecting your sleep – both how much light you see during the day (and when) and whether there are light sources in your sleeping area. This is because light sets your circadian rhythm, which is responsible for setting a whole host of other biological responses in motion.

Your brain does not know whether it is day or night, and your brain does not know whether that light is artificial or real. Therefore, light communicates to the brain anytime it enters your eye. Your body automatically responds by increasing your heart rate and blood flow and activating your nervous system. Furthermore, that light registers even when your eyes are closed.

Light communicates to the brain anytime it enters your eye. Furthermore, that light registers even when your eyes are closed.

Does the Type of Light Matter?

Blue light resembles sunlight and is disruptive to sleep patterns. It can delay melatonin’s release, making it difficult to fall asleep. A blue light filter helps combat this, and many can mimic the activity of the sun in your time zone.

One experiment compared the effects of 6.5 hours of exposure to blue light to exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms by twice as much.

Red light is the best if you must have light; perhaps that is why so many alarm clocks have a red digital display. Red light has no impact, and yellow and orange light have little effect, so these are great color choices for your bedroom’s night lights or alarm clocks.

Is it worth it to invest in changing the type of light in your bedroom?  Let’s look at the long-term effects of light on your health. 

What Are the Long-Term Effects of Light on Your Sleep and Your Health?

Unfortunately, there are many adverse effects on your sleep and your long-term health when you are exposed to light when you sleep. 

A recent study by Phyllis Zee, MD, Ph.D., chief of Sleep Medicine, A Northwestern Medicine physician, found that disturbing circadian rhythm with exposure to light made it harder to regulate blood glucose levels. Disrupting the sleep-wake cycle affects the pancreas’ ability to secrete insulin appropriately.  Just a small amount of light activated the autonomous nervous system, even though the study subject was sleeping with their eyes closed.

Disrupted circadian rhythms are also linked to obesity, depression, seasonal affective disorder, and diabetes.

Fortunately, there are straightforward ways to deal with light in your bedroom.

 How to Handle Light Sources in Your Bedroom

Some sources we can control; others we cannot. The first step is to check your bedroom for sources of light that are not necessary. If you must have a nightlight, avoid white or blue light. Instead, go for more of a red or orange light and keep it close to the floor. Some of our adjustable bed models have built-in floor lamps.

For many reasons, it is good to keep devices out of the bedroom since the blue light from electronic devices can stimulate your brain and make it think it is daytime.

If you live in a place with outside sources of light that shine into your bedroom, such as street lights, blackout curtains, or blackout shades can help. If that does not work, an eye mask can be helpful, or try moving the bed so that you are not directly in the light. These solutions can also benefit people who work a night shift and must sleep during the day.

It takes a little work to put solutions into practice, but the effect on your sleep and health will be well worth it. Rest is one of the pillars of good health, and keeping light out of your bedroom is one of the significant ways to ensure you get a refreshing night of rest.