Last week, a review of studies published in the Cochrane Database of Systematic Reviews, one of the most popular platforms in the scientific world, called into question the effectiveness of advertised glasses capable of filtering out blue light (the light emitted by electronic equipment). The review was conducted by the University of Melbourne, Australia, in collaboration with researchers from Monash University, also in the country, and the University of London, in the UK, and analyzed data from all 17 existing randomized controlled trials on the topic. from six different countries including Australia, the Czech Republic, Japan, Norway, the United States, and the United Kingdom.
The authors concluded that there is no conclusive scientific evidence to support the recommendation of blue light filtering lenses for the general population in order to protect the eyes from blue light, reduce eye strain or improve nighttime sleep quality.
As explained by ophthalmologist Tiago César Pereira-Ferreira, Professor of Ophthalmic Surgery at the Faculdade Ciências Médicas de Minas Gerais (FCM-MG) who specializes in contact lenses, cataract, refractive surgery and keratoconus, the benefits that this type of glasses promise are meaningless. Scientifically speaking.
Screen light and natural light
“The claim that blue light is harmful to the eyes is because it is the closest thing to UV rays, but there is no definitive evidence that UV rays cause damage to the eyes. Furthermore, the amount of blue light coming from artificial sources such as computer screens is about 1,000 times less than that from natural daylight, and blue light filter lenses retain only about 10 to 25% of this light,” explains Thiago César Pereira-Ferreira.
In order for these lenses to provide these benefits, according to Tiago Cesar, they need to be significantly darker: “The review of studies also did not find convincing evidence that these lenses actually reduce eye strain and improve sleep, which are the main promises.” of these products.
is reading: Screens: cause irreversible damage to the development of infants and children.
The ophthalmologist also recommends limiting the use of electronic devices before going to bed and maintaining a dark and quiet environment. To control eye strain, he leaves out another piece of advice.
The main strategy is to follow the “20-20-20” rule, which involves looking away from the screen every 20 minutes, and focusing on something 20 feet (about 6 meters) away for 20 seconds. Keeping them clean and using adequate lighting are important practices.