Blue light glasses, also called blue light filtering or blue-blocking lenses, are sold to reduce eye strain from screens, improve sleep and protect your eyes. The College of Optometrists says there is no strong evidence that they do any of these things for most people.
That does not mean screen discomfort is imagined. Long spells of close work can leave your eyes tired, dry or achy. The evidence points to other causes and other fixes, and an eye test is a good place to start.
What the research found
In 2023 a Cochrane review of 17 randomised controlled trials compared blue light filtering glasses with ordinary lenses. The College of Optometrists reported its main findings:
- There may be no short-term benefit for eye strain from computer use compared with ordinary lenses
- There was little or no effect on how clearly people could see
- The effect on sleep was unclear
What UK eye care bodies advise
The College of Optometrists says opticians who sell blue-blocking lenses should tell patients there is no strong evidence that they improve vision, ease eye strain or improve sleep, and that it is unclear whether they protect the macula. The Association of Optometrists says there is no clear evidence that blue light from screens causes eye disease, and notes that the blue light from most devices is a small fraction of what your eyes receive outdoors on a sunny day.
What can help with screen discomfort
If screens leave your eyes tired or uncomfortable, these steps are more likely to help:
- Have an eye test. An uncorrected or out-of-date prescription is a common cause of strain, and some people benefit from glasses set for computer distance
- Take regular breaks and look into the distance from time to time
- Remember to blink. People blink less when concentrating on a screen, which can make eyes feel dry
- Set your screen at a comfortable distance and reduce glare from windows and lights
- Put screens away a while before bed, since evening screen use may affect sleep
Should you buy them?
If you like how blue light filtering lenses feel, there is no evidence they do harm for most people, but you should not expect them to fix eye strain or sleep problems. If you use a screen for work, ask your optometrist whether a separate pair of glasses for screen distance would help. If you use display screen equipment as a significant part of your job, the Health and Safety Executive says your employer must provide an eye test on request, and pay for a basic pair of glasses if you need them specifically for screen work.
