Do you think wear glasses may weaken your eyesight? Keep reading…There are many reasons why people don’t usually wear glasses. Maybe they don’t like how they look with them, maybe they are teased or simply feel more comfortable without them.
But beyond the comfort and aesthetics, some fear that the frequent use of glasses weaken your eyesight and you will depending on them at the end more often than the first time you used them.
A study in Nigeria that was published last year revealed that 64% of students believe that wearing glasses can cause eye damage. Research in the Indian state of Karnataka put the figure at 30% and in Pakistan, 69% of people who think the same way. In Brazil, even medical staff believe that the eyes become weaker as a result of the use of glasses.
Is there any evidence that they are right?
Where does the myth come from?
There are two different reasons why people wear glasses: the difficulty for distance or myopia, when distant objects are blurred, and the difficulty of nearsightedness or farsightedness, when nearby objects cannot be focused.
The difficulty for nearsightedness is normally related to aging: Many people who are between 40 and 50 years begin to notice that they have difficulty reading in low light.
As we age, the lens of our eyes gradually hardens, making it more difficult to see different distances.
When people reach the stage where your arms are not long enough to hold a book or a menu to a distance necessary to focus on the text, choose to use reading glasses.
What is surprising is that there have been few studies on the effect of using longsighted lenses. And there is no conclusive evidence that the use of reading glasses affects the way you see in a negative way.
So why so many people are convinced that the glasses have worsened their eyesight?
It is possible that people rely increasingly on their glasses, but this is because the lens will continue to deteriorate with age.
And, realising that they need their glasses more frequently some people conclude that the glasses have worsened his view, when in fact, there is no causal relationship.
The decision of whether to use reading glasses or not, will not affect in any way your long-term vision (even if you have to strain your eyes to read and might have headaches or feel irritated eyes).
However, the situation is not the same with children.
Failure to use the proper or not use them at all if needed glasses, can have a long term impact.
For decades it was believed that an insufficient correction of myopia, to provide glasses children with a lower ranking than actually needed, could delay the elongation of the eyeball with time and, therefore, slowing the progression of myopia.
The idea was that if you needed glasses to see clearly, the eyeball would be extended when the person is focusing on a nearby object in order to see properly, but a test in Malaysia in 2002 showed that this hypothesis was wrong and the experiment had to be stopped a year earlier than planned.
Each of the members of a group of 94 children with myopia were randomly assigned using the appropriate prescription for glasses. At the start of the study, children were aged between 9 and 14 years and the length of his eyeballs was measured at regular intervals over the next two years.
Unlike a previous smaller study in the 60s, children who wore glasses lower ranking showed increased elongation of the eyeball time. In other words, his eyesight was deteriorating gradually.
Children as indicated
Some argue that there is not enough evidence to reach firm conclusions.
However, a Cochrane review conducted in 2011 regarding intervention studies in children with myopia concluded that the limited available evidence indicates that it is better to give children the right glasses, instead of trying to intentionally prescribe a lower graduation.
The correct prescription reduces the risk of strabismus. There is nothing to indicate that the use of appropriate eyeglasses worsens vision compared to not using them at all.
In fact, the largest study to date on the progression of myopia, which has just published its conclusions 23 study indicates otherwise. In 1983, a group of Finnish children with myopia were randomly assigned to various conditions, including reading without glasses. Their myopia progressed a little faster than those who used their glasses continuously. After the first three years of the study they were advised everyone that will use glasses all the time. Twenty years later, there was no difference between groups.
The benefits of using glasses for a child who needs them, are obvious. The eyes of the children have to learn to see, so if you do not have the right glasses can develop the so-called “lazy eye” or amblyopia, because they have never displayed a clear image on the retina.
It has also been shown to improve correct prescription reading speed and reduces the risk of strabismus.
Why there are not more studies about eyesight?
There is no reason to think that wear glasses hurts the eye, but back to adults, what I find curious is the lack of studies that have been conducted in this area.
It is hoped that science has all the answers, but sometimes the studies that seem the most obvious to perform have not been performed.
Those studies about eyesight that require children to wear glasses myopia are not unethical because of the effects that are known to have on school performance and the developing eye.
But in principle, this type of study could be carried out in adults hyperopic or myopic. Therefore, we are left with the question of why no one wants them.
Professor Ananth Viswanathan, surgeon at Moorfields Eye Hospital in London, believes that the lack of research is probably due to the absence of physiological reasons that the glasses may cause eye damage. The research not only needs to look for associations, but also plausible mechanisms.
So, apparently, no such studies will take place in the short term.
Meanwhile, we will continue with the anatomical evidence. And while there are many reasons to choose not to wear glasses, fear they could be causing damage to the eye is no longer one of them.