Is Apple’s Brightest Phone Ever a (Bigger) Threat to Your Health?
Apple’s new iPhone 17 has caused Twitter’s EMF watchdogs to erupt in protest. Engineers increased the iPhone’s maximum screen brightness to 3,000 nits, a 50% boost over prior phones. In theory, the risks to the new iPhone users from artificial blue light — from cataracts to endocrine disruption — have increased by half. Is Apple in fact run by psychopaths?
Exposure to isolated blue light is toxic to humans, causing circadian misalignment, skin aging, and a cell stress response that increases insulin and blood glucose. Food gurus, pontificating about low carb diets and blood sugar, drive up their insulin instead by sitting inside all day on their phones. Studies that use outdoor light at night as a proxy for overall “light pollution” find that blue light is an environmental carcinogen.
In fairness, Apple designed its handheld inferno to ignite only in the brightest of conditions — likely found outdoors. Under these circumstances, circadian disruption is moot and natural sunlight overpowers the hazard of blue-lit screens.
Apple phones also come with screen control features that every user should activate.
Flicker
Flicker refers to the rapid, repetitive variation in the brightness of an artificial light source. For example, visible flicker is found in a florescent blub about to die; other forms of flicker are too fast to notice consciously though the brain still detects them. The health effects from flicker include headaches, migraines, and eye strain. For what it’s worth, the only flicker-free light source is the sun.
Cellphones use Pulse Width Modulation (PWM), a significant source of phone flicker, to quickly switch pixels on or off to control the brightness that users perceive. The iPhone 17 introduced a new accessibility option called “display pulse smoothing” that lets users disable PWM. You can toggle the phone to use only steady light:
- Settings > Accessibility > Display & Text Size > Pulse Width Modulation
Blue Light
Apple allows users to 1) lower overall light intensity, and 2) lower the ratio of blue light by shifting the color balance.
1) The Reduce White Point setting dims whites and colors without changing the ratio of colors to one another. It is included on all modern iPhones:
- Settings > Accessibility > Display & Text Size > Reduce White Point
2) The Night Shift setting actively filters blue light by shifting the display’s color temperature toward warmer tones. It can reduce blue light output by up to 80% at maximum warmth:
- Settings > Display & Brightness > Night Shift
Using both settings together provides the most comprehensive reduction of blue light.