Over 2.2 billion people around the world face some type of vision problem, including 12 million Americans over age 40. Of these, 1 million are legally blind.
But what causes blindness? Does someone become blind later in life or are they born without vision? And how do we know when vision changes call for concern?
In this article, we explore the most common causes of blindness in children and adults, including the biggest risk factors to pay attention to.
We answer questions like:
What are the early symptoms of vision problems?
What causes blindness in children?
What causes blindness in adults?
Who is at risk of blindness in adulthood?
What are the symptoms of age-related macular degeneration (AMD)?
What are the symptoms of cataracts?
What are the warning signs of diabetes-related retinopathy?
What are the symptoms of glaucoma?
What are the symptoms of retinal detachment?
When should I see a doctor about vision concerns?
Where can I get more information about blindness?
What are the early symptoms of vision problems?
There are several vision changes that could hint to a bigger problem. Some appear over time while others occur all at once.
Early symptoms of vision loss might include:
Double or blurry vision
Seeing flashes of light, floaters, halos, rainbows around lights, or what looks like a curtain coming down over one eye
Sudden or new sensitivity to light
Difficulty seeing at night or in bright light
Eye pain
Itching, burning, or red eyes
White areas in the pupil
Changes in the color of your eye
Who is at risk of blindness?
Those with a higher risk of developing blindness include people who:
Have had a stroke
Live with an eye disease like glaucoma or macular degeneration
Live with diabetes, especially if it’s uncontrolled
Need or have had eye surgery
Work with chemicals and sharp objects or in dangerous environments
Are born premature
Carry a genetic link to blindness like Usher syndrome
Develop dangerous illnesses like severe infections or swelling in the brain
Do race, sex, age, or other demographics impact the risk of blindness?
Some demographic factors do play a role in your risk of blindness. These include:
Medical insurance status.
Financial status.
Employment. People who work in dangerous conditions like factories or construction sites are more likely to have eye accidents than someone who works in an office or retail store.
Level of education. People with less education are six times more likely to develop eye conditions compared to people with higher education. This is because education often determines someone’s availability of healthcare or their long-term financial status.
There is no documented connection between race and blindness, unless your race puts you at a higher risk of developing conditions that can lead to vision complications.
For example, people of African, Native American, and some Asian or Pacific Islander ancestries have a higher risk for diabetes, which can cause eye problems if left untreated.
What causes blindness in children?
The most common causes of blindness in children include:
Congenital cataracts (cataracts present at birth)
Severe vitamin A deficiency
Infections like meningitis, the measles, or the rubella virus
Inherited retinal disorders or birth defects
Childhood glaucoma
Nerve damage, like optic nerve or cerebral impairments
Trauma during birth or premature birth
Accidents, particularly those that cause trauma to the eyes or brain
What causes blindness in adults?
The five most common causes of blindness in adults are:
Age-related macular degeneration (AMD)
Cataracts
Diabetic retinopathy (also called diabetic eye disease)
Glaucoma
Retinal detachment
Trauma, like eye injuries or traumatic brain injury, is also a common cause of adult blindness, particularly for people who live or work in dangerous environments.
What are the symptoms of age-related macular degeneration (AMD)?
Age-related macular degeneration, or AMD, is an eye disease that impacts your central vision. We see things directly in front of us through central vision, so while people with AMD lose that ability, they may still be able to see via their peripheral (side) vision.
In its early stages, AMD symptoms usually go unnoticed. As macular degeneration progresses, however, people with AMD might experience:
Poor night vision
Blurry vision
Changes to color vision
Dark spots in the center of their vision
Seeing straight lines as wavy or curved
To learn more about macular degeneration, see Macular Degeneration: Seven Quick Facts You Should Know.
What are the symptoms of cataracts?
A cataract is a film-like, cloudy spot that appears in the eye’s lens. Like AMD, initial cataract symptoms may go unnoticed.
Over time, people with cataracts may experience:
Cloudy or blurry vision
Faded color vision
Poor night vision
Light sensitivity, especially sunlight or headlights while driving
Halos around lights
Double vision
Early detection is key to treating cataracts, although surgery may remove cataracts causing severe vision problems.
To learn more about cataracts, see Do I Have Cataracts? Cloudy Vision, Faded Colors, and Other Symptoms of Cataracts.
What are the warning signs of diabetes-related retinopathy?
Diabetic retinopathy, also called diabetes-related retinopathy or diabetic eye disease, is a complication of poorly managed diabetes. Like many eye conditions, diabetic retinopathy has no symptoms at first, but can progress quickly.
Warning signs of diabetic retinopathy include:
Streaks or small dark spots in vision
Blurry, double, or distorted vision
Difficulty telling the difference between colors
Poor night vision
What are the symptoms of glaucoma?
Glaucoma refers to fluid buildup in the eye that eventually damages the optic nerve, the nerve that sends visual signals to the brain.
There are two main types or stages of glaucoma: open-angle and angle-closure glaucoma.
Open-angle glaucoma often carries no symptoms. It involves minor damage to the optic nerve which can only be seen in an eye exam.
Angle-closure glaucoma occurs when there is a “glaucoma attack.” A glaucoma attack brings symptoms like:
* Sudden blurred vision
* Severe headache and eye pain
* Nausea and vomiting
* Halos or rainbow rings around lights
Glaucoma treatment involves both medication and surgery. To learn more about glaucoma, see Glaucoma: Symptoms and Early Signs.
What are the symptoms of retinal detachment?
Often painless, retinal detachment occurs when a part of the back of the eye called the retina pulls away from the rest of the eye.
There are three types of retinal detachment:
Rhegmatogenous retinal detachment, when a small tear appears in the retina. This type is often age-related.
Tractional retinal detachment, usually caused by diabetes.
Exudative retinal detachment, usually the result of eye inflammation.
Retinal detachment symptoms usually occur suddenly. They might include:
Sudden flashes of light
Sudden dots, squiggly lines, threads, or dark spots that move across your vision
Darkening of your side vision (peripheral vision)
Shadows covering or darkness appearing in part of your vision
Retinal detachment can usually be treated with surgery, but some severe cases can cause permanent or total blindness.
When should I see a doctor about vision concerns?
Any major changes to your vision, the way your eyes look, or how your eyes feel mean it’s time to visit your eye doctor. In particular, eye pain or sudden vision loss are major indicators that something could be wrong.
In addition, get an appointment with your eye doctor ASAP if you experience any of the following emergency vision symptoms:
Sudden vision loss in one eye
Sudden blockage in your eye, or a feeling like a curtain dropped over your vision
Rainbows or halos around lights
Blurry or hazy vision that appears out of nowhere
Black spots or flashes of lights
Loss of side vision (peripheral vision)
Where can I get more information about blindness?
To learn more about blindness, see:
To find organizations that support people who are blind, check out Ability Central’s Service Locator tool. This searchable national database of nonprofits can help connect you with a local organization offering medical services, social programs, or other support for people with vision disabilities.
Additional Information
The content provided in this article is for informational purposes only and is not intended as a substitute for legal, medical, or other professional advice. While we strive to provide accurate and up-to-date resources, some information may become outdated or incomplete. Always consult with your provider about personal medical concerns.
