Gary L. Morgan, OD, focuses his blog on AMD prevention, strategies for monitoring patients with AMD, the effects of blue light on the retina and mitigating the unforeseen effects of technology on vision and overall health. He is in private practice at Eye Tech Associates in Arizona.

Disclosure: Morgan is an advisory board member for Arctic Dx, MacuHealth and Signet Armorlite.

BLOG: Reducing blue light at the source

A couple of months ago, Apple released its latest operating system, iOS 9.3, which includes Night Shift. With blue light in the 460 nm to 490 nm range being shown to reduce melatonin secretion and hence adversely affecting circadian rhythm, solutions to reduce exposure to these wavelengths are being looked at. There are two ways this can be approached.

First, it is possible to filter blue light in those wavelengths with spectacle lenses. However, to get any significant blockage, current technology would dictate the lenses would need to be a dark brown color – not very practical when being used at night. It should be noted that there are also no clinical studies that show how much blue light must be blocked with lenses to affect melatonin secretion. Likewise, there are no available lens products on the market that are clinically validated to enhance sleep. However, anecdotally, I have had patients and have had colleagues tell me that some of their patients report an easier time falling asleep while wearing current en masse lens technology.

The second way to achieve blue light reduction at night is to reduce exposure at the source. And that is where apps like Apple’s Night Shift come in.

I recently had an opportunity to sit down with my classmate and noted blue light authority, Thomas Gosling, OD, and we discussed the pros and cons of Night Shift.

Thomas Gosling

Thomas Gosling

GM: What are your initial thoughts on Night Shift?

TG: There have been apps on the market well before Night Shift that addressed the blue light issue with backlit screens. What I find interesting is that Apple as a company has stepped up and incorporated Night Shift into its operating system. I think this reflects the awareness that the blue light topic is receiving worldwide. Seeing Apple give users an option to control the amount of blue light being emitted from their screens is a great first step.

GM: What exactly does Night Shift do?

TG: Within the settings of the iPhone’s display and brightness, Night Shift can be activated. When active, Night Shift changes the color temperature of the display to a warmer color or more of a reddish hue vs. the typical bright white. By making this shift, the amount of blue light can be significantly reduced. When in the Night Shift settings, you can control the warmth of the display. When the slider is positioned to the far right or to “more warm,” less blue light will be emitted.

GM: Do you have any suggestions on how to make it better?

TG: I think for their first go around, Apple did a good job implementing it into their operating system. Sliding up the shortcut bar from the bottom gets you to Night Shift quickly, but you have to go into your settings to actually make changes to Night Shift’s display properties. Having the ability to change the color temperature on the fly would help users utilize night shift more frequently.

GM: I understand you produced a video to help patients, especially parents, maximize the benefit of Night Shift. Can you tell me about that?

TG: I have for the longest time explained to my patients the benefits of turning down their phone’s brightness, especially at night, to help with sleep and the effects of blue light to the eyes. In the video, I show the amount of blue light coming off the iPhone screen using a blue light sensor. Changing the brightness and utilizing Night Shift can have a significant effect in reducing blue light emission. Watching the video really brings a better understanding of just how significant the effect is.

Here is the link to Thomas’ video, great for directing patients to, putting on your website or in your waiting room video loop.