First question: Do you use inexpensive LED bulbs in the lights you turn on in the evening and at night?
Next question: How is your sleep going? Deep and refreshing? If so, that’s terrific—you can stop reading now.
If you do have sleep issues, your LED bulbs are likely contributing to them big time. The cause is the blue light they emit.
For billions of years, all life on the planet has been structured around the 24-hour cycle of light, the earth’s circadian rhythm—blue sky in the day and darkness at night.
“Blue light from the sun has been the key day-night signal ever since life began deep in the blue oceans,” says Martin Moore-Ede, M.D., a.k.a the Light Doctor. “If you go below 200 meters [660 feet] in the ocean, all you see is blue light when it is daytime and pitch darkness when it is night.”
Our brains, through our eyes, adjust to sunlit days and dark nights. The amber light of fires, candles, and oil lamps of our distant ancestors had no blue light and did not disrupt their circadian clocks. But 200 years ago, the lights that electricity gave us began taking over our nights, our homes, and our cities—even our cars. These lights emit blue wavelengths nearly as bright as daylight. They gave us the night hours to work and study, build and play. And we innocently didn’t know any better.
Now we know better. In the last 20 years, thousands of studies have shown that blue light at night is a major contributor to sleep and health problems.
The Role of Melatonin
Blue light from sunlight is good, energizing—and necessary, in fact. A study in Sweden found that women not getting outdoors in sunlight doubled the risk of poor health.
As darkness descends in the evening, the hormone melatonin begins to be produced by the brain. It starts the changes in your brain that prepare you to settle into the deep, refreshing sleep your body needs.
“Melatonin’s central role is to serve as a signal of biological night, which helps keep all the cells in the body in sync with the light-dark cycle,” says Moore-Ede.
The blue in daylight suppresses melatonin—that’s its daytime job. Then, at the end of the day, as the sun sets and the blue of daylight fades into the dark of night, the body is free to produce melatonin to settle us for sleep. By morning, our brains have cleaned us of melatonin and other hormones that helped us sleep, and the blue of the morning light wakes us up.
Or, that’s how it’s supposed to work.
How Blue Light Disrupts
When, after dark, the blue light in our bulbs suppresses melatonin, it halts the brain’s preparation for sleep. The blue in light bulbs, especially in the inexpensive LED bulbs, shuts down the production of melatonin and disrupts our body’s built-in circadian clocks.
“In the absence of the natural day-night cycle, which the blue in lights at night disrupts,” says Moore-Ede, “the precisely timed circadian clocks in our body drift out of sync with each other so we live in a state called ‘circadian disruption,’ making us much more vulnerable to illness and disease. The greater the light exposure at night, the greater the risk of serious illnesses such as obesity, diabetes, heart disease, and breast and prostate cancer.”
As just one example, the breast cancer rate in women night-shift workers, who work all night under artificial light, is 50 percent higher than it is in daytime women workers.
Most people know that the screens on our computers, tablets, iPads, and phones emit blue light. Unfortunately, the night shift settings on our devices don’t yet block enough blue light to help us sleep. Several companies now offer screen protectors that give an untinted picture, yet block almost all the blue light being emitted from the screens.
Blue-Blocking Bulbs & Light Fixtures
The good news is that we can now buy blue-blocking light fixtures for our homes, schools, hospitals, and cities. Several companies produce bulbs that have no or almost no blue yet are still very bright—or emit amber light that allows for working and reading in the evening.
I’ve tried bulbs from several companies, and my home is now bathed in an amber glow in the evening, with plenty of light to work. And my sleep is better. If I get up in the night, the little blue-light blocking rechargeable lamp in my bath turns on with a touch.
These are the companies I’ve found so far that produce technically verified blue-light blocking bulbs and screen protectors. Low-blue bulbs can be subject to flickering, but I haven’t yet had that problem with these brands.
Soraa ZeroBlue bulbs produce a white spectrum light, giving white light in the evening rather than amber. Soraa.com, (855) 632-6736.
Ocushield’s Ocubulb. I have ordered screen protectors as well as pale amber bulbs from them. To go deep, you can download their very informative Blue Light White Paper: Ocushield.com, email hello@ocushield.com.
BlockBlueLight’s BioLight has a day mode and two amber evening modes. You change light levels by turning your light switch on and off, so you don’t need dimmable light fixtures. BlockBlueLight.com.
Further Resources
Visit the “Friends of the Night Sky (Jefferson County)” Facebook group for more in-depth reading. When we change our city lights, we will get our starry nights back, too.
I also recommend Dr. Moore-Ede’s book The Light Doctor. For four decades, he has been the leading researcher and activist on the problems posed by blue light. At his Circadian Research Lab, he researches the effect of blue light on health and sleep.