What are cataracts?

Cataracts are caused by a build-up of protein that clouds the eye’s lens, which can lead to blurred vision and eventual blindness.

A man has his eyes checked for trachoma in Ghana.

Cataracts are an eye condition caused when the lens of the eye develops cloudy patches. Over time these patches usually grow bigger, causing blurry, misty vision.

There are different types of cataracts, depending on which part of the eye’s lens is affected: they can affect the centre, the sides, or the back of the lens. They can appear in just one eye or in both eyes, although they may not develop at the same time. Eventually, if they’re not treated, cataracts can lead to blindness.

What causes cataracts?

Cataracts are caused by a build-up of protein in the eye, and usually develop because of old age. However they can also appear as a result of eye injuries or following eye surgery for other problems. They can also be present from birth: in many poorer countries, where healthcare and treatment may be less readily available, childhood cataracts can be a major cause of blindness.

A close-up of a boy's eye, showing the clouding of the lens caused by a cataract.

How do cataracts affect vision?

What does the world look like when you have cataracts? Our simulator will give you an idea.

Try the simulator
12.6 million
people are blind because of cataracts
cataract operations were supported by Sightsavers in 2020
can pay for an adult cataract operation

What are the symptoms of cataracts?

  • Blurred, dim or misty vision
  • Difficulty seeing in low light or at night
  • Sensitivity to light: lights look too bright or glaring
  • Colours look faded or muted
  • Seeing a ‘halo’ around bright lights
  • Everything looks more ‘washed out’

If you have cataracts, things can start to look dim, blurred or distorted, as if you’re looking through dirty glass. Your vision may seem cloudy, and it can also be hard to make out details or colours.

Try our vision simulator to see what the world looks like when you have cataracts.

Winesi a 69 year old man, hugs his wife and smiles after his cataract operation.

A Million Miracles

Our campaign raised enough money to provide a million cataract operations.

About the campaign

How are cataracts treated?

Surgical staff perform a cataract operation.

Cataract operation

Cataract surgery for adults is carried out under local anaesthetic. The procedure usually takes as little as 20 minutes to complete.
Watch a time-lapse of the surgery

A close-up of the plastic lens that's implanted into the eye during a cataract operation.

Replacement lens

During the operation, the clouded lens is removed and replaced with an artificial lens. If a patient has cataracts in both eyes, they will have separate operations for each eye.

Recovery after surgery

After cataract surgery, the patient’s vision starts to return within a few hours. After post-operative checks, their bandages are removed and they can usually go home the same day.

Our work to treat cataracts

Sightsavers aims to make it easier for people to be treated for cataracts, especially in poorer countries where surgery is not always readily available.

We also want to improve the quality of cataract surgery and increase the number of operations that are able to be performed.

To achieve this, we aim to improve community health programmes and increase the number of surgeons, nurses and community workers trained in eye health, as well as educating people about cataracts and explaining where to get treatment.

Since our work began in 1950, Sightsavers has helped to provide 7.9 million cataract operations in poorer countries, and trained more than 1,020 surgeons to perform the operations.

But we need your help to save the sight of people with cataracts: donating to our charitable cause can help to change lives. An eye examination to screen someone for a range of eye conditions costs less than a cup of coffee, and could be the first step towards restoring their vision.

Zamurrad holds a hand up to her eye, while both her and her daughter smile at the camera.

Zamurrad’s story

Zamurrad’s life ground to a halt when she developed cataracts, but a straightforward operation gave her back her independence.

Read her story

Donate and help us save sight

I would like to make a donation

could buy instruments, dressings and pharmaceuticals for five cataract operations.

could pay for life-changing cataract surgery for four adults.

could pay for sight-saving operations for two children with cataracts.

We're sorry, but the minimum donation we can take is $3
We're sorry, but we cannot process a donation of this size online. Please contact us on [email protected] for assistance donating over $15,000

could pay for replacement lenses for four children with cataracts.

could restore the sight of an adult suffering from cataracts.

could pay for a life-changing childhood cataract operation.

We're sorry, but the minimum donation we can take is $3
We're sorry, but we cannot process a donation of this size online. Please contact us on [email protected] for assistance donating over $15,000

More about cataracts

A collage of images featuring men, women and children wearing glasses.
Sightsavers from the field

World Sight Day 2021: highlights from around the world

On 14 October 2021, Sightsavers staff, partner organisations and supporters celebrated World Sight Day to raise awareness about the importance of access to good eye care.

October 2021
A man wearing sunglasses smiles with his two happy grandchildren.
Sightsavers Reports

“Now I can see again, I can make money to support my family”

Father and grandfather Sardar from Pakistan is the main breadwinner for his family. But his children and grandchildren faced an uncertain future when he began to develop cataracts.

Sightsavers blog

“What do we mean by the global eye health crisis?”

In an interview for World Sight Day 2021, Sumrana Yasmin, Sightsavers’ global technical lead for eye health, talks to Mutave Mutemi about her work, the global eye health crisis and how we all have a part to play in addressing it.

Mutave Mutemi, October 2021

Learn about our work to save sight