In this article, we bring the latest in scientific research to an age-old question: does habitual wearing of glasses make your eyesight any worse?
Much of the credit to this old tale comes from the belief that glasses make your eyes lazy – allowing your eyes to ‘take it easy’ rather than straining the tiny muscles that control the shape of the eye lens (the bit of the eye responsible for focusing things clearly, so they aren’t blurry) as you would do without glasses. As a result, your eyes become ‘lazy’, and your vision without glasses declines.
In the words of Stephen Taylor, an Opthalmic Consultant in Boston, the theory above is “more myth than reality.” So keep a hold of your glasses – they definitely don’t make your vision worse.
Understanding this is a matter of understanding what makes vision better – or worse – in certain individuals. First up, there’s straight up ‘short-sightedness’, known medically as myopia. Making distant objects blurry (while retaining the clarity of close-up objects), myopia can be caused by a huge range of different factors. Ultimately, what is clinically referred to as simple myopia – the most common kind – is caused by eye being too large for the lens, so focussed rays do not hit the retina, but converge before it. In other words, the lens is too strong for the eye. A 2006 study concluded that myopia could affect as many as 2.3 billion people around the planet.
The role of glasses is to correct the power of the lens, often by focussing light divergently before they hit the over-convergent lens of the eye. In this way, light hits the retina just as it should, and everything is seen in focus.
So does not wearing glasses help to keep your eyes ‘in shape’? Definitely not, conclude several studies. The Bates Method is a popular therapy among alternative medicine specialists. It involves a series of eye relaxation and strain exercises, designed to improve the flexibility of the eye. All clinical trials involving the Method, though, have failed spectacularly. There is no evidence that these exercises influence the acuity of the eye one iota.
Further studies into eye exercises – such as a 2005 one conducted by a group of scientists from the Ophthalmology Department of Christchurch Hospital in New Zealand– suggest that working the eye hard by refusing appropriate eyecare has absolutely no positive effect whatsoever. Eye exercises, it seems – including those ones accidentally incurred by not wearing glasses – do not help to improve your vision, while appropriate eyecare does.
So where does the myth come from? Partly from alternative medical practices like the Bates Method, for sure. But there is a good reason why people may perceive their eyesight to worsen with glasses. It’s a condition called presbyopia.
Presbyopia happens to all of us as we get older. Between the ages of 40 and 50, the lens of our eye becomes flatter, bigger and weaker. As a result, those muscles around our lens – the ones responsible for stretching and shaping it – become slacker and weaker. Straining without glasses does not help, as the strain is taken up by the more tense ligaments connecting the center of the lens to the rest of the eye. Presbyopia leads many people to get glasses in the first place, and because it gets worse over time they might think that the glasses are somehow the source of the worsening. They’re not. Unfortunately, presbyopia is chronic – it gets worse over time – and inevitable. But, hey, at least we can manage it with glasses, safe in the knowledge that we’re not harming our vision.
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