There are no eye exercises or special diets that prevent the normal worsening of eyesight as we age. It is a natural deterioration. The medical term for difficulty seeing things that are in close proximity is called presbyopia.

It usually starts by needing to hold books or newspapers further away to make out the words. Almost everyone will need reading glasses after reaching the age of 45, according to Informed Health, an authoritative website on health matters.

Seeing clearly is the result of the eyes lenses changing shape and focusing light onto the retina. A muscle is responsible for adjusting the shape of the lens, either flattening it or making it thicker.

But as we age, the muscle becomes weaker and the lenses less flexible. This is what causes most people to need reading glasses.

Informed Health, which is run by a publicly funded German institute, the IQWiG, recommends seeing an optician for a vision test and getting adjusted prescription reading glasses, rather than opting for those bought off the peg at a drugstore.

Although the drug store glasses are cheaper, they do not take into account that the eyesight is likely different in both eyes. – dpa