The Latest LED Tech Promises Warmer Hues and a Better Night’s Sleep

New lighting products, including from Casper, offer warmer color temperatures, which affect circadian rhythms and wellness in general.
LED sleep technology

Glow, a new lighting product from Casper, offers warmer color temperatures, which affect circadian rhythms and wellness in general. Courtesy of Casper


A host of new lighting products claims wellness, mood lighting, and a better night’s sleep—all at the flick of a switch or the tap of a smartphone screen. Using the latest LED technology to adjust the light’s color temperature, companies ranging from giant GE to mattress start-up Casper are marketing color as the next frontier in domestic wellness. But what is color temperature? And why would someone want to control it?

Though it’s measured in degrees Kelvin, color temperature is not concerned with physical warmth, but rather with quantifying the color of a lamp. (Higher “temperatures” correspond with cooler hues—think the icy illumination from an open fridge.) Until recently, LEDs were available only in pure white and cool blue, but advances in technology in the past ten years have introduced LEDs with lower color temperatures that produce a warmer, yellower light more akin to that of an incandescent lamp. Pablo Pardo of lighting studio Pablo Design calls these developments a “tipping point” for LED technology because they enabled designers to specify a range of color temperatures, from roughly 2,700 to 6,500 K, for various applications.

The high color temperature of a standard LED, which emits a bluer light, works well for the office or environments that demand focus, but a mounting body of evidence suggests that blue light, especially in the evening, disrupts our production of melatonin, a hormone that helps us sleep. The latest generation of smart lighting seeks to put users back on a natural cycle by glowing increasingly yellow through the evening.

For Marty Brennan, associate principal at the Seattle offices of ZGF Architects, lighting systems attuned to the body’s circadian rhythms are especially useful in health-care settings, where natural light can help patients relax. Systems for the home and office also allow adjustments on demand, often via a smartphone app, though ironically, smartphone screens are a notorious source of blue light. It could be that high-tech, circadian rhythm–synced LEDs will help you sleep better—but only if you can put down your phone.

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Categories: Lighting Products