Blue Light and Cancer
Last week, we received an interesting question from a customer about blue light and cancer. She wrote:
“There are studies showing that the blue light spectrum in LED lights are harmful especially for breast and prostate cancer.
I wanted to get your feedback on this.”
As you may know, I’m fascinated by how light affects the body, so I love it when customers send interesting links like this or post it on our Facebook, etc. Although I am not a medical doctor, I do enjoy reading about the effects of light.
Before reading the article in her link, my knee-jerk reaction was that blue light could do harm if it is used at the wrong time of the day. I have heard of some studies linking nighttime exposure to blue light to a variety of health problems.
In the case of the eyes, over a long period of time, exposure to intense blue light is suspected of causing damage to vision.
And blue light is involved in regulating circadian rhythms. Although many do not realize how important circadian rhythms are to our health and immune system, my doctor has explained it to me before and they are vital to our health and well-being.
I have noticed other studies that have linked night-time blue light exposure to other health problems, such as disruption of circadian rhythm. While I do not have a lot of knowledge about cancer, I do know that my own physician advised me to avoid excessive blue light exposure at night because it interferes with circadian rhythm and impairs the immune system.
My own speculation on the subject is that humans were meant to have more blue/white light exposure in the morning time, not at night. In the morning, the blue-green wavelengths in sunlight are what trigger the body to stop melatonin production and to wake up for the day.
Exposure to blue wavelengths at night would likely interfere with melatonin production, harming quality of sleep. Melatonin is also a powerful anti-oxidant, so losing it would not be good for someone battling a disease with immune system involvement such as cancer.
Over time, it makes sense that repeated suppression of melatonin could contribute to health problems- even diseases as serious as cancer.
To us, the problem seems to be the time of blue light exposure. Even people with no health problems might want to avoid intense blue light at night and limit any exposure to it to the morning or early afternoon. And of course, everyone should shield their eyes from any intense light, which we always recommend when using any of our bulbs.
What I recommend is only using our blue or green bulbs only in the morning or early afternoon. Using them at night might be acceptable if eye protection is worn the entire time. Using them in the morning ensures you’re getting blue/green light at the proper time of day that won’t interfere with your melatonin production and getting good-quality sleep.
It’s not that all blue/green light is bad- it’s not. It’s just that there’s an optimal time to use it and using it at the wrong time could cause unintended effects (like difficulty sleeping).