One of the things about getting older that is a constant, many times daily, reminder of the fact, is presbyopia. That is, the loss of the ability to read or view a computer screen without glasses. We have all sorts of cute names for these hated devices including 'cheaters' and 'close ups', and we ladies buy them in cute leopard patterns with matching cases.
What Causes Presbyopia?
Presbyopia is caused by an age-related process. This differs from astigmatism, nearsightedness and farsightedness, which are related to the shape of the eyeball and are caused by genetic and environmental factors. Presbyopia generally is believed to stem from a gradual thickening and loss of flexibility of the natural lens inside your eye.
These age-related changes occur within the proteins in the lens, making the lens harder and less elastic over time. Age-related changes also take place in the muscle fibers surrounding the lens. With less elasticity, the eye has a harder time focusing up close. Other, less popular theories exist as well.
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