Presbyopia: why your arms suddenly feel too short after 40

It usually starts with a menu in a dim restaurant. Then the back of a medicine box. Then your phone, which you find yourself holding a little further away than you used to — and it works, so you keep doing it.

This is presbyopia. It is not your eyes getting weak, and it is not something you brought on by using your phone too much. It happens to everybody who lives long enough.

What is actually changing

Inside your eye, behind the pupil, there is a clear lens. When you look at something far away, it sits relatively flat. When you look at something close, a ring of muscle around it lets it become rounder, which adds focusing power. That shift is called accommodation, and it is how you switch from the road to your dashboard without thinking about it.

That lens becomes gradually less flexible over a lifetime. The change starts far earlier than most people notice — it is a slow, steady loss from childhood onward. What happens in your forties is that the remaining flexibility finally drops below what you need for reading distance. Nothing sudden happened in your eye. You simply crossed a line.

Which is why holding the page further away works: at greater distance, less focusing power is required. Your arms are doing the job your lens no longer can.

The signs, in the order they usually arrive

• Small print is fine in bright light and impossible in a dim room — your pupil narrows in bright light, which deepens your range of focus
• You need to push the phone or the book further out
• Your eyes ache or your head feels tight after reading, even when you could read it
• Text is clear for the first minute and blurs the longer you look
• Looking up from close work, distance takes a second or two to come back into focus

It shows up earlier if you already wear glasses for long-sightedness, and later if you are short-sighted. Some short-sighted people find they can read comfortably by taking their distance glasses off entirely — that is real, and it is also a clue about your prescription rather than a solution.

Does it keep getting worse?

Yes, and then it settles. Reading correction typically increases through your forties and fifties, then stabilises. This is why people who buy off-the-shelf readers find themselves buying a stronger pair every couple of years. The change is in the lens inside your eye, not in the glasses.

The other thing worth being clear about: reading glasses do not cause the progression, and avoiding them does not slow it. Straining without correction just gives you headaches. It buys you nothing.

What it does not explain

Presbyopia is gradual, affects both eyes, and only affects near vision. It does not explain sudden blur, blur in one eye only, distance vision that has gone soft, or a reading change that arrives over weeks rather than years. Those need an eye test promptly — several unrelated conditions can change near vision, and some of them are time-sensitive.

Book a Vision7 eye test at your nearest Vision Express store

Our seven-step comprehensive eye exam measures how much near correction you actually need rather than guessing from your age, and the binocular eye exam checks that both eyes are still working together at reading distance — which is what off-the-shelf readers cannot account for, since they give both eyes the same power and the same optical centre.

Ask for Essilor Varilux Physio Extensee at the counter. It is a progressive lens, so distance, screen and reading all sit in one pair — no swapping glasses to read a menu, and no line across the lens. The benefit for someone newly presbyopic is a wide, stable intermediate zone, which is the distance your phone and laptop actually live at.

If you spend most of your day on dual monitors, ask about Shamir Autograph Intelligence, which gives the widest working corridor for desk distances.

Every pair comes with free lifetime ultrasonic cleaning, free lifetime custom fitting and adjustment, and a 1-year warranty.