Cataracts: causes and symptoms

Lesley Dobson / 25 July 2016

Cataracts are a common sight problem that is more likely to affect us as we grow older. Learn more about the causes and symptoms of cataracts.



Cataracts can develop because the lens in your eye slowly changes as you age. The lens sits right behind the iris – that’s the part of your eye that makes it blue, brown or any other colour.

The lens is really important to our vision because it directs light onto the light-sensitive retina at the back of the eye. This then turns the light into electrical signals. Then nerves send the signals to the brain, which turns these into the images you see.

This process only works if the lens is clear. Once the lens starts changing, it’s harder for the light to go through it. When the lens becomes cloudy it means that it has a cataract, and this will start to affect your vision.

Identifying common eye problems

Cataract symptoms

Your sight probably won’t be as clear as it was, but you may also have other symptoms. These can include:

  • Cloudy or blurred eye sight
  • Finding bright lights – like car headlights - painful or difficult to look at
  • Finding colours much duller than usual
  • Seeing everything with a yellowish tinge

Causes of cataracts

The most common cause of cataracts is growing older. Most of us aged 65 or more have changes to our lenses, which are likely to develop into a cataract.

While age is the main cause behind the development of cataracts, there are other reasons why they develop. These can include having diabetes, taking particular medicines – for example steroids - and having previous eye surgery for other reasons.

There are some lifestyle factors that may contribute to cataracts developing, including smoking, and spending long periods of time in the sun. Research is still being carried out in these areas, so we don’t yet know for definite whether they are a cause of cataracts.

10 tips for eye health

How to find out if you have a cataract

You may develop a cataract in one eye before the other. This can make things appear different in the affected eye – headlights may be more dazzling, your sight may be more blurred, and again, everything in that eye may have a yellowish tinge.

When you realize that you’re having trouble seeing as well as you used to – even with glasses - see your optician. They have specialist equipment – for instance an ophthalmoscope – that lets them look into your eye to check for cataracts.

Is it time for an eye test?

What happens next if your optician thinks you have a cataract

If they feel that you do have cataracts, your optician will refer you to an ophthalmologist – a specialist in this field. They will examine your eyes, and if they agree that you have a cataract, the surgeon will arrange for you to have cataract surgery.

Learn more about cataract surgery

The opinions expressed are those of the author and are not held by Saga unless specifically stated.

The material is for general information only and does not constitute investment, tax, legal, medical or other form of advice. You should not rely on this information to make (or refrain from making) any decisions. Always obtain independent, professional advice for your own particular situation.