Per the AMA, LED lights emit an unseen blue light that can disturb sleep rhythms and possibly increase the risk of serious diseases like cancer and cardiovscular disease. Had you heard that?

If it is unseen, how do we know it is blue? Also, who sleeps with the lights on? And what do a bunch of doctors know about LED light?

Blue light is entirely in the visible spectrum so that does not make sense about the unseen part. However LED are based on blue light, that is true, there are fewer wavelengths in LED light than in natural light so a particular blue has a higher ratio than is normal. I think most people sleep with no light anyway.

No.

"unseen blue light" that would be ultraviolet i suppose, potenially harmful in large doses (eg: tanning all day) but harmless if powered by just a LED.

Frankly this sounds like you are quoting the national enquirer.

It's not that the blue light is "unseen". If it's blue, of course we can see it. The problem is our sleep cycle is regulated by light. Bluer light is what we see in the daytime. So when we see it later at night it's preventing our brain from producing melatonin, which makes you want to fall asleep. But it is a real health concern. Lack of sleep is becoming a problem everywhere, and it affects many aspects of health.

I found a serious article about it: https://www.washingtonpost.com/national/health-science/some-cities-are-taking-another-look-at-led-lighting-after-ama-warning/2016/09/21/98779568-7c3d-11e6-bd86-b7bbd53d2b5d_story.html

Not an Enquirer scare story, but neither is it as alamist as your question sounds.

PS: all white light have blue light as a component. by mixing blue, red and yellow light we get light that looks white.

Here is a link to what Rosie is referring to. 

http://www4.toledoblade.com/Medical/2016/09/26/Health-warning-issued-on-LED-lights.html

"LIKE"

An unseen light in a visible color that causes physical diseases. I think that is what they call "quack medicine". Or magic. The AMA has never been known for espousing either.

In submarines they switch to blue lights while it is night time outside.

Thank you for your questions Ele and Happy Monday.

Thank  you for your reply JakobA and the link! :)

 Thanks  honey. I don't know how to do that and I appreciate it a lot that you are watching my back! Thank you for your reply and the link Karen and Happy Monday! :) ((hugs))

Thank you for your reply Rpf and Happy Monday! :)

You're welcome Rosie. :) Glad I could help.

((HUGS))

I assume you don't know.

Have you ever been in one?

Actually as an experiment to this question I used a large  prism and observed both incandescent and fluorescent lights. Neither has a spectrum. Sunlight does, however.

in essence the article was about those high density, very bright street lights.

No, I read the book written by a crewman on the first cruise to the north pole.

You just have to peek through the windows after sunset.