Exposure to artificial light during the hours of darkness is a serious yet often ignored health risk. Blue wavelengths can be particularly disruptive, and they are believed to contribute to both sleep disorders and metabolic disorders.
And, with our growing use of electronics and the increase in energy-efficient lighting, we are exposed to more artificial blue light than ever. Luckily, there are several ways to reduce our exposure to this light, including through the use of blue light blocking glasses.
What is Blue Light?
Blue light wavelengths are found in both natural light (i.e., sunlight) and artificial light.
Exposure to blue light during the day, as nature intended, actually provides us with a number of health benefits. It helps to increase our attention, improve our reaction times, and boost our mood. When balanced with other colors of light (such as red wavelengths from the sun), blue light plays a role in resetting our internal clock.
However, increased attention and energy are not so helpful after dark, when we should be winding down and preparing for a restorative night of sleep. But due to computer and smartphone screens, energy-saving light bulbs in the home, grocery store, and street lamps, we are continually subjected to blue light after the hours of darkness.
To counteract this, some people put on a pair of blue light blocking glasses once the sun goes down. Is it a good idea?
7 Reasons to Wear Blue Light Blocking Glasses at Night
1. Regulate Melatonin Production
Melatonin is a hormone that plays a vital role in controlling the body’s circadian (daily) rhythm.
When the sun sets, melatonin is released into the bloodstream. It helps us to wind down and feel sleepy, with melatonin levels remaining high for 12 hours throughout the night. Then, exposure to daylight causes levels to fall until they are barely detectable—and you are fully awake and ready for a new day!
Of course, artificial light interferes with the natural rise and fall of melatonin levels. Although all light has an effect, blue light wavelengths are especially disruptive.
Harvard researchers compared the effects of over six hours of exposure to blue light with exposure to green light. They found that blue light suppressed the production of melatonin and disrupted circadian rhythms for twice as long as green light.
Other research found that filtering out blue light during the night enhanced total sleep time and sleep efficiency in shift workers (nurses) when compared with those exposed to standard indoor light. In addition, melatonin levels were significantly higher during night shifts in the nurses exposed to filtered light.
2. Enjoy Better Sleep
By regulating your melatonin levels, you will naturally set up your body for a better night’s sleep.
When twenty adults were given either blue light blocking glasses or UV light blocking glasses, it was found that those with the blue-blocking pairs enjoyed a significant improvement in sleep quality and mood.
It should be noted that even a small amount of light can be problematic. Just eight lux, which is less than that emitted by a standard table lamp, can impact sleep — highlighting the importance of reducing light exposure wherever possible during the hours of darkness.
3. Control Cortisol Release
Like melatonin, cortisol is a hormone. It’s involved in many processes in the body, including blood sugar and blood pressure control. It’s also known as the “stress hormone” as extra cortisol is released in response to stress.
Cortisol is generally released in the morning, with levels falling throughout the day and night. However — although the relationship between cortisol and blue light is complex — some research suggests that cortisol production increases due to exposure to light during the middle of the night.
4. Reduce the Risk of Serious Illness
As you can see, blue light exposure at night affects sleep, the body’s internal clock, and the release of hormones. It’s unsurprising, then, that it can set you up for some serious health conditions including:
- Heart disease
Although the research into blue light and illness is limited, it is thought that lower melatonin levels are linked with cancer. Also, altered circadian rhythms can increase blood sugar and reduce a hormone called leptin that regulates the feeling of fullness after eating.
5. Protect your Eyes
According to some, blue-blocking glasses prevent damage to the eyes by protecting a fatty acid called DHA in the retina – the light-sensitive tissue at the back of the eyeball.
Having healthy levels of DHA ensures proper retinal function. It also protects against damage from exposure to bright light and the oxidative stress found in those with eye diseases.
6. Manage Shift Work Patterns
People who work the night shift have dysfunctional circadian rhythms and disruptions in melatonin production. Therefore, they are at higher risk of certain illnesses including cancer, heart disease, digestive problems, and obesity.
Wearing blue light blocking glasses at night could help shift workers regulate their melatonin production and internal body clock, and therefore minimize disruptions to their sleeping patterns.
7. Treat Mania in Bipolar Disorder
Bipolar disorder is a mental health condition characterized by extremes in mood, ranging from emotional highs, called mania or hypomania, to depression.
Research published in 2016 reports that even one week of wearing blue blocking glasses led to improvements in sleep and a reduction in symptoms of mania in people with bipolar disorder after just three days.
The researchers were surprised by the magnitude of changes and how quickly they were noticed, especially as drug treatments typically take longer to take effect.
Although promising, it should be noted that the group studied was very small and more research is needed in this area.
Choosing Blue Light Blocking Glasses
Blue light blocking glasses are a worthwhile investment for everyone, but especially for shift workers, those who have difficulty sleeping, and people with metabolic disorders or mental health issues.
There are many types of blue blocking glasses, also known as amber glasses, on the market. Although inexpensive sunglasses with orange lenses may filter out blue light, they also block other colors, making them unsuitable for use indoors.
These blue light blocking glasses by Swannies block harmful blue wavelengths at night while still letting in other types of light. They are ideal for use when on the computer or tablet or while watching TV. At a minimum, they should be worn for 90 minutes before bed, but feel free to put them on once darkness falls.
Other Ways to Avoid Blue Light at Night
Blue light blocking glasses are just one of the ways to encourage a healthy circadian rhythm and regulate your body’s hormone levels. Other ways to do this include:
- Reduce or avoid exposure to TV, computers, tablets, and smartphones after dark. Learn more about the damaging side effects of smartphone use.
- Avoid LED streetlights, or wear your blue-blocking glasses to filter out blue light from these lamps.
- Install a blackout blind in your bedroom and turn off all sources of light, including clocks with an illuminated display. Wear an eye mask to block out any unavoidable light sources.
- Use an application like f.lux on computers and tablets to automatically reduce the screen’s levels of blue light once darkness falls.
- Swap your lamps for ones with orange or dim red bulbs at night time. Or, better yet, use a salt lamp. As well as providing a soothing glow, it purifies the air.
- Get enough natural light during the day. You’ll not only ensure a good night’s sleep, but you’ll avoid vitamin D deficiency. For best results, get some early morning sun by walking to work or eating your breakfast outdoors. About fifteen minutes exposure should be enough to wake you up and kickstart your internal body clock. Where possible, get another hour of sunshine at noon.
Use Blue Light Blocking Glasses for Better Sleep and Health
For healthy sleeping habits and optimal health, try using a pair of blue-blocking glasses during the hours of darkness. Many studies suggest that you will see benefits after just a few nights of use.
By using these glasses, you’ll regulate the release of cortisol and melatonin, two powerful hormones that impact sleep-wake cycles, mood, stress responses, and metabolism. Blue-blocking glasses can also protect your eyes from the damage caused by exposure to television, computers, and smartphone screens.
To maximize the benefits of your new glasses, be sure to get enough sunshine during the day, block all light from your bedroom while sleeping, and limit screen time before bed.