Eyewear companies have been aggressively marketing lenses designed to block blue light emitted in high concentrations by smartphones, tablets, computer screens and TVs. Example: The company Felix Gray will add a blue-light ­filter to a pair of glasses for $95. The claim: Blue-light-blocking lenses help to prevent sleep disruptions, eyestrain, even macular degeneration. Is it help or hype?

BLUE LIGHT AND YOUR HEALTH

There’s no question that evening exposure to blue light interferes with sleep, but other claims are iffy. There’s no credible evidence that blue light from screens is a major cause of eyestrain, and one much publicized study showing macular degeneration–related retinal damage from screens involved rats, not people.

Plus, we need blue light. It’s found in sunlight and enhances daytime functioning by boosting attention, reaction times and mood. In fact, blocking blue light all day could mean that you will have a tough time waking up.

SLEEP SOLUTIONS

It’s true that having a special pair of glasses with blue-light-blocking lenses that you wear only in the evening might improve sleep. But there are other ways to accomplish this…

Dial back your exposure to bright light from your smartphone, computer screen, tablet, etc., about 90 minutes before bedtime. To do this, either stop using these devices or turn down their brightness.

Change your lightbulbs. While old-fashioned incandescent bulbs emit very little blue light, compact fluorescent and even standard LED bulbs emit plenty. Instead, try Good Night LED lightbulbs, offered by Lighting Science. They transform blue light into warmer colors using a technology developed by NASA to help astronauts on the International Space Station get their ZZZs.