Myopia: Debunking Myths & The Surprising Benefit

“Ideal for giving your eyes a break from the blue light of screens.“says a advertising slogan online that promotes an optician in Argentina. The phrase clearly shows the inaccurate message in which, almost from one day to the next, this little piece of the light wave spectrum – blue light – became involved, perhaps after some famous person stated that they had started taking care of their eyes with a filter. blue blocker.

Based on the global warning about deterioration of eye health in children and adolescents, it is worth clarifying some misunderstandings about the relationship between eye health (specifically, myopia) and blue lightwhich does not by definition do harm, nor does it come only from electronic devices nor is it stopped with yellow or orange lenses, as some believe.

The focus on myopia and blue light It has another reason: there is a worrying projection for 2050, according to which 40% of children will be myopic. It came out in a paper British Journal of Ophthalmologyin September 2024, titled Global prevalence, trend and projection of myopia in children and adolescents from 1990 to 2050: a comprehensive systematic review and meta-analysis and conducted by researchers from China.

The authors conducted a systematic review of 276 studies on more than 5.4 million children and adolescents from 50 countries, which ended up showing that childhood myopia has not only been increasing steadily since 1990 but has affected, a year and a half ago, 30% of children in the world. Based on these figures, the projection for 2050 is that 740 million children and adolescents will be myopic.

The question is what to do with this. That is, if it is an unavoidable destiny or it can be avoided that the children of the house fall into the bag of the 3 out of 10 (or, in the future, 4 out of 10) who could develop myopia during the course of primary or secondary school.

It is comforting to know that, contrary to the notion that genetics “is everything”, certain environmental factors (mainly lifestyle, and at this point blue light matters a lot) direct the issue, to the point of being almost decisive in whether or not a person ends up wearing glasses.

Of course, it is a field “under exploration,” explained Esteban Travelletti, head of the Pediatrics and Strabismus section in the Ophthalmology division of the Hospital de Clínicas. Although he shared with Clarion scientific publications that warn of the weight of genetic predisposition in the risk of developing myopia (it is twice higher in children with a myopic parent, and five times higher, with both myopic parents), the statistics of myopia associated with lifestyle habits are only beginning to be known.

Even so, Travelletti raised the importance of raising awareness among the population about how to avoid acquired myopia. He shared key concepts and strategies and, along the way, weeded out a couple of misconceptions about eye health.

Given that the prevalence of childhood and adolescent myopia has increased so much in recent years, the most appropriate question may be what of everything we do today on a recurring basis we should avoid. The doctor explained it.

On the one hand, he raised a generalized problem: “Screens are talked about as the central cause of myopia, but in reality the problem is constantly focusing closely on something, without looking up to vary the distance of what you are looking at.”

The issue matters because “the myopic eye is one that has become so adapted to looking up close that, in some way, it has resigned itself to distant vision.” Why is this happening? “The blur produced by seeing so much up close stimulates the eyeball to grow, stretch and deform, which generates poor distance vision,” the doctor clarified.

In addition to ending up wearing glasses in many cases, the problem he highlighted is that myopia is also a risk factor for other pathologies: “Mild myopia is not the same as high myopia, which can predispose to retina problems, cataracts and strabismus, since a weakness occurs in different structures of the eye.”

In summary, the indication to avoid the emergence of myopia in minors or the worsening of an already established condition is to take pauses, or as Travelletti said, “break down, interrupt close vision and look from a distance every so often, exactly the same thing that one does by changing the posture of the body when sometimes you spend a long time reading hunched over and want to avoid deforming your spine.”

Negotiating screen hours with children is not always easy, considering that “many school assignments today happen through Zoom or digital platforms,” the ophthalmologist admitted. However, you can intervene in how these devices are used, he noted.

For example, positioning the screens at a greater distance, so as to demand a different focus from the eye. If it is a desktop computer, Travelletti recommended that the screen be about 50 to 80 centimeters away, if possible. If it is the television, two or three meters away is ideal. “I prefer that the child rest from the cell phone watching TV, rather than continue looking at the phone a few centimeters away,” the doctor said.

Another very little-disseminated central point is that it is “super proven” – he said – that “good ambient lighting and, above all, natural light, slow the progression of myopia.” So much so, he clarified, that “children who are outdoors for at least two hours a day are much better off in terms of myopia than those who are not.”

The explanation is that natural light stimulates the release of dopamine, a known hormone, which is essentially the same as that produced with physical activity (and which lifts the mood almost immediately), but in this case, since it is produced inside the eye, it operates or functions differently.

“More natural light, more dopamine. And what it does is simply stop the excessive growth of the eye,” which precisely tends to cause myopia, he clarified. For this reason, “classrooms with windows and good natural light contribute to a lower incidence of myopia cases in children.”

Although the harms of children spending the entire day in front of the phone or tablet are known, the first myth to banish is that it is the screens that, in effect, cause vision problems (although, as is known, they can interfere with the production of melatonin, which can complicate sleep).

“Screens are no worse than books, in that sense,” the doctor compared. As an argument, he invoked the classic stereotype of the “traga”, that ultra-studious reader who always wears glasses. “Now it seems that all kids are lazy because they wear glasses, whether they like to read books or not,” he said ironically.

The other big misunderstanding is influence of blue light In all this, one of the various parts of the visible wave spectrum, which it should be noted is not only present on screens but also in the sun. In recent years, the idea (for doctors, not very deep) that blue light “does harm” has been established. Filters that block it and promise to protect eyesight proliferated, with which the optics industry managed to install a captivating product on the market.

In case there is any doubt, these filters are transparent, with an almost imperceptible bluish tone, and have nothing to do with the yellowish or orange-toned filters, also in fashion these days, but used to see with greater contrast and at night.

Travelletti, who clarified the whole question of blue light, clarified that the alarm about these rays arose from a series of studies in cell cultures in which, when cells were illuminated with intense blue light, damage was observed. From there “it was extrapolated and proposed that blue light must damage the retina, without conducting large clinical studies to support the issue.”

Conversely, he stated the opposite, and said that blue light is good for people with myopia. “To the extent that it is part of the broad spectrum of sunlight, blue light is associated with slowing eye growth in myopic children. And in fact, natural light has a lot of blue light. The idea is that the patient is exposed to the entire spectrum of natural light,” he noted, and clarified that, of course, “that does not mean unprotecting oneself or exposing oneself to harmful radiation in the middle of the day.”

As for the blue light from screens, Travelletti noted that it is not bad for the nearsighted (on the contrary), but he was cautious about those with small eyes (“the farsighted”). Although “more studies are needed on this matter, in these cases it might be preferable to avoid blue light.”

In addition to the two hours a day outdoors and frequently varying the focus (avoiding spending long hours without interruption on something very close), Travelletti shared a second combo of strategies that he uses in his office. They are “medical interventions that are chosen once myopia is established and progresses.”

The first is the pharmacological route: “Basically, atropine diluted or in very low concentrations. Applied in drops, it prevents the eye from growing excessively. This proposal is used, with medical monitoring, in the pediatric population and adolescents.” The purpose of the drug: slow down the pace which increases myopia.

The other treatment is completely optical, thanks to a type of special lenses that “correct central vision and modify peripheral focus.”

They are designs in which, by the way, the center of the lens in the glasses has the correction for the necessary degree of myopia, but the peripheral part, on the other hand, has a controlled blur, which (due to an optical effect that is quite complex to explain) induces the growth of the eyeball to slow down. As the specialist concluded, “it can be said that it is a blur that also slows the progression of myopia.”