Cataracts are the leading cause of age-related vision decline, but they can be more complex than you might think. Cataracts, cloudy or hazy spots that form on an eye lens, are most commonly linked to old age but can also be a result of untreated diabetes, injury, or a range of other health conditions.

This article answers seven frequently asked questions about cataracts, including:

• What is a cataract?
• What are the causes of cataracts?
• What are the types of cataracts?
• Are cataracts genetic?
• What are other common vision changes with age?
• Do cataracts cause sudden blurry vision or sudden floaters in one eye?
• How do cataracts affect day-to-day life?

What is a cataract?

A cataract is a treatable cloudiness that forms on the eye’s usually clear lens. Most cataracts appear as a part of growing older, and many do not require immediate treatment. However, untreated cataracts can cause vision problems or vision changes like:

• Hazy, cloudy, or blurry vision
• Faded or yellow-tinted colors
• Light sensitivity
• Night blindness
• Nearsightedness
• Double vision
• Halos

Most of the time, cataracts that alter vision do not get better with prescription glasses. Instead, the most common treatment for severe cataracts is surgery to remove them. 

What are the causes of cataracts?

The eye's lens is a clear, flexible structure made of proteins called crystallins. Around the age of 40, these proteins naturally begin to break down and form clumps. The result is a cataract, a cloudy, hazy, or filmy substance that covers the eye’s lens. 

Most cataracts are a natural part of getting older. While cataracts may begin forming in someone’s 40s or 50s, cloudy vision and other symptoms typically do not appear until age 60. 

However, younger people or people with underlying health conditions can still develop cataracts. Other risk factors for cataracts include:

• Diabetes
• Eye injury or surgery
• Radiation or chemotherapy treatments
• Smoking
• Steroid use
• Sun damage from not wearing proper UV sunglasses

What are the types of cataracts?

There are four primary types of cataracts:

• Nuclear cataracts affect the center of the lens.
• Cortical cataracts affect the edges of the lens.
• Posterior subcapsular cataracts affect the back of the lens. 
• Congenital cataracts, also called or pediatric cataracts, are cataracts a person is born with, or that develop in infancy. 

To learn more about the symptoms of each cataract type, see Do I Have Cataracts? Cloudy Vision, Faded Colors, and Other Symptoms of Cataracts.

Less common types of cataracts include:

• Anterior subcapsular cataracts, which develop on the front of the lens and are caused by eye injury, inflammation, or irritation.
• Christmas tree cataracts, made of colorful spots on the lens shaped like a Christmas tree. This most often occurs in people with myotonic dystrophy. 
• Secondary cataracts, also called posterior capsule opacification (PCO), which can occur after a cataract surgery.
• Snowflake cataracts, which cause white spots shaped like snowflakes to form on the lens. They are rare and usually only affect young people with Type 1 diabetes.

Are cataracts genetic?

Cataracts are often genetic. Although the most common cause of cataracts is old age, cataracts that affect young adults and children have led researchers to believe cataracts may also have a genetic factor. 

You should get your eyes regularly tested for cataracts if:

• There is a history of cataracts in your family, especially if a close relative (like a parent or sibling) has cataracts. 
• There is a family history of diabetes.
• There is a family history of other eye diseases, like diabetic retinopathy, macular degeneration, or glaucoma. 

Other than cataracts, what are the most common vision problems?

Besides cataracts, vision problems are often the result of age-related conditions, retinal diseases, or refractive errors. 

Aging and vision problems sometimes go hand in hand. In addition to cataracts, other age-related vision problems include:

• Age-related macular degeneration (AMD), which causes blurred or distorted central vision but does not cause total blindness.
• Glaucoma, which is caused by increased pressure inside the eye. If left untreated, it can lead to permanent vision loss and blindness. 

Retinal diseases are another form of eye disease that can cause vision problems unrelated to age.  Retinal diseases include:

• Diabetic retinopathy, which can lead to blood vessels leaking in the eye due to uncontrolled blood sugar.
• Macular degeneration, when the center of the retina deteriorates, causing problems with central vision.
• Retinal detachment, when fluid collects under the retina, causing it to detach from the underlying tissue.
• Retinitis pigmentosa, an inherited disease that slowly causes night and side vision loss.

While some people are near-sighted or far-sighted for much of their lives, refractive errors are common vision changes with age. Refractive errors include:

• Myopia, or near-sightedness. 
• Hyperopia, also called farsightedness. 
• Astigmatism, when the shape of the cornea warps and distorts vision at all distances.
• Presbyopia, the loss of the ability to focus up close, which typically appears between the ages of 40 and 50.

To learn more about vision issues, see Ability Central’s catalog of Low Vision resources.

Do cataracts cause sudden blurry vision or sudden floaters in one eye?

Cataracts cause slow, progressive vision changes that are monitored through regularly scheduled eye exams. You should see your eye care professional as soon as possible if you notice sudden vision problems, including:

• Double vision 
• Flashes of light
• Sudden eye pain
• Sudden headache

These may be signs of more serious eye conditions like diabetic retinopathy or macular degeneration. 

How do cataracts affect day-to-day life?

Cataracts can cause vision to be blurry or less vivid, but they can also cause almost complete blindness. As vision worsens, someone with cataracts may require help to get around or complete everyday tasks like driving, cooking, and cleaning. Communication, particularly visual methods like texting, emails, or writing letters, can be much more difficult. 

Many people with cataracts benefit from mobile devices that are equipped to handle their changing vision.

Ability Central maintains a wide database of mobile devices designed with the limitations of cataracts and low vision in mind. Whether you need a larger screen, voice-dictation ability, or hands-free options, there is sure to be a device that meets your needs.

Where can I get more information about cataracts?

To learn more about cataracts, see:

• Do I Have Cataracts? Cloudy Vision, Faded Colors, and Other Symptoms of Cataracts
• Cataract Surgery: Resources for Cataract Treatment and Diagnosis
• Cataracts: Costs, Care, and Long-term Challenges