Glasses which filter out blue-light probably make no difference to eye strain from computer use, according to a new Cochrane review of available evidence.
Blue-light filtering glasses are widely advertised and optometrists may recommend or prescribe the specialised spectacles based on the belief they reduce visual fatigue from computer screens.
Digital technologies and modern lighting emit relatively higher amounts of blue light than traditional light sources, giving rise to the theory that blue-light filtering lenses may assist with screen related eye concerns.
However, the review of evidence published in the Cochrane Database of Systematic Reviews did not support the use of the specialised eyewear for eye strain compared to regular glasses.
University of Melbourne Associate Professor Laura Downie directs a Cochrane Eyes and Vision Centre for Evidence-Based Vision Care and is an author of the study.
She says the main finding is “based on research to date, it doesn’t support the prescription of blue-light filtering lenses to the general population for the purpose of reducing eyestrain.”
The paper reviews the findings of 17 randomised controlled trials across 6 countries which compare the blue-light filtering glasses with regular glasses. Studies range from 5 to 156 participants, and for periods between 1 day to 5 weeks following use of the glasses.
The finding that blue-filtering glasses make little to no short-term difference is “low certainty”, because there is some evidence showing no effect, but more research is required in the form of consistent, larger and high-quality studies in diverse populations.
“There are clear missing pieces of information that require further research to better understand the potential role of these lenses,” Downie says.
She adds the potential effects on sleep are also unclear due to the lack of consistent evidence relating to sleep quality from wearing the lenses before bedtime.
The review also did not identify any consistent serious adverse side effects from wearing the blue-light filtering glasses.
Side effects where identified, including discomfort, headaches and lower mood, were generally mild, infrequent and temporary, and likely to relate to wearing glasses generally rather than specific to the blue-filtering kind.
Downie says, “if someone is experiencing eyestrain, their first port of call should be to make an appointment with their eye care health professional. In that appointment, they would be expected to have a thorough examination of their eye health as well as how their eyes are functioning. Sometimes there may be an underlying eye health or vision problem that’s contributing to the eye strain.”