As an eye specialist with around 20 years’ clinical experience, I have prescribed thousands of pairs of spectacles to people in their middle years for near work; mainly for reading. Nothing remarkable in that in itself but the range of ages when people first present with near work problems is interesting; to me anyway. These are my observations.
People who have spent many years living in hot and sunny climates, particularly if they have worked outside a lot, have been exposed to a lot of cumulative UV and UV is known to change the protein structure of the crystalline lens. This is turn makes the lens less flexible so it can no longer change shape to become curved enough to allow clear focus at near. These people are likely to need spectacles for near work at a much earlier age than those who have worked and lived in cooler environments with low levels of sunlight; as early as mid-to-late 30s.
People who are tall tend to have longer arms than those people who are not tall. Long arms are useful with insipient presbyopia as items can be held further away until they are in the range where lens flexibility is enough to produce curvature that allows reasonable clarity. People with long arms may be able to push back the need for near spectacles several years. Of course, the time will be reached when the person’s arms aren’t long enough or things have to be held so far away that they become too small to see.
In the UK we do strange things to the time twice a year. In the Spring, at 2 am in the morning on a certain day in March everyone changes their timepieces to 3 am. In the Autumn, at 2 am in the morning on a certain day in September everyone changes their timepieces to 1 am. I won’t go into the reasons for this here. The Autumn change causes an increase in profit for people supplying spectacles because the nights get darker an hour sooner. This means that people who were just about coping with their insipient presbyopia because daylight was improving their depth of clear focus through a smaller pupil now have less daylight to help them. Many homes are so poorly lit with artificial lighting that this is no substitute for daylight. People struggle to read and make an appointment for an eye examination. Many of my colleagues look forward to the Autumn clock change and the boost it brings to their businesses.