Let there be no light before bed
If reading in bed is something you've always done, you may want to think twice about using your smartphone or tablet for your nighttime reading. This week on “Take Care,” WRVO's weekly health and wellness show, hosts Linda Lowen and Lorraine Rapp speak with Dr. Lois Krahn, a psychiatrist with the Sleep Disorders Clinic at Mayo Clinic Arizona, about how too much screen time could be disturbing your sleep.
Linda Lowen: Screens are ubiquitous and I do hear a lot of parents talking about limiting their children’s screen time. But with regard to ourselves as adults, I hadn’t realized how detrimental they could be to the sleep habits that we have. What is it about these screens and the light that they emit?
Dr. Lois Krahn: Recent discovery has been that blue light effects sleep and affect the brain more so than white light. And most of these devices do emit blue light. It doesn’t look blue, but the wavelength is in the blue range. So a blue light that is directed at the eyes does turn the brain on in a way that promotes alertness, and at bedtime you don’t want to be alert.
Lorraine Rapp: So the habit of reading in bed is something you suggest changing when you’re reading from your iPad or whatever device you have. What is your advice – is there an actual range, like a dimness facture, where there’s a threshold you don’t cross, but you can still read from your tablet.
Dr. Krahn: Well, the absolute safest approach is the old-fashioned book or magazine. But many people are no longer purchasing those items, so they have to figure out how to make the iPad work, because they no longer get the newspaper in a paper form, they read it on their iPad. So hold it at least 16 inches away from one’s eyes, and take advantage of the dimmer that all of these devices now have and be sure that the light is dimmed to 50 percent, or I would actually say as low as you can manage and still read the material on the illuminated screen, is the preferred way to do this.
Lowen: So this would not apply to anything that advertised itself as a paper-white screen. In other words, if it’s backlit, if you can read it in the dark, it’s a danger. If you can’t read it in the dark, it’s not a problem.
Dr. Krahn: I think that’s a pretty safe assumption. You know, the challenge is this technology is changing. And I do think the manufacturers are going to try their best to try to come up with a solution. But just be careful, not so much about the color of the light, because we cannot detect the wavelength, the blue wavelength. I would say the easiest thing to pay attention to is the brightness. And you can adjust that in two ways: distance from your eyes and dimming the actual light emitting from the device.
More of this interview can be heard on "Take Care," WRVO's health and wellness show Sunday at 6:30 p.m. Support for this story comes from the Health Foundation for Western and Central New York.