What are Cataracts: Treatments, Causes, & Risks

Written By: Susannah Lockett

Worldwide, cataracts are the number one cause of vision loss. The condition occurs when the eye’s lens becomes cloudy. This is most often due to aging, especially in people over 40, although cataracts can have other causes, too. Whatever the reason, cataracts are treatable.

Cataract Causes

The eye’s lens lies behind the iris. Along with the cornea, it helps to focus light correctly on the retina at the back of the eye. It also helps the eye to focus on objects near and far. To do its job, the lens must remain clear.

The lens is composed mainly of water and protein. As some people age, these proteins can clump together, causing the usually clear lens to turn opaque and no longer let light through. 

Over time, these clumps can obstruct the clear lens more and more, making it harder and harder to see. The exact mechanism of this process is poorly understood, but there are some known risk factors associated with the development of cataracts

Cataract Risk Factors

UV radiation from the sun
High blood pressure
Statin medications (for high blood cholesterol)
Chronic use of steroid medications
Previous eye injury, inflammation, or surgery
Excessive consumption of alcohol
Family history
High myopia
HRT (hormone replacement therapy)
As you can see, many of these risk factors are at least controllable. Another preventative measure you can take is to increase your intake of fruits and vegetables. 

These contain antioxidant compounds thought to prevent certain oxidative changes that may lead to the development of cataracts. Studies have shown that these antioxidants may help prevent certain types of cataracts. 

You can also ask your eye care professional about supplements containing vitamins C and E, lutein and zeaxanthin, and the trace minerals copper and zinc. These may help give some extra antioxidant power to your diet. 

Symptoms of Cataracts

Cataract symptoms take many months to years before they become apparent. There may be little to no visual change for a long time. However, as the cataract grows and clouds up the lens more and more, visual acuity becomes less and less. 

Typically, one of the cataracts’ first symptoms to appear is blurry vision, a bit like trying to peer through glass that’s opaque or not totally clear. While cataracts can occur in just one eye, they’re more likely to appear in both. 

However, the two cataracts won’t necessarily progress at the same rate. This may produce different symptoms in each eye or even no symptoms in one but significant ones in the other. Other cataract symptoms include:

Light seems more bright than it used to
You notice your eyes are more sensitive to light than usual
Colors may look washed out
Hazy, dim, double, or blurry vision
During night driving, oncoming headlights seem to glare more 
Halos around bright lights
Vision at night or in low light seems to be impaired

An advanced cataract may be visible to others. It will show as a light gray or bluish area where the black pupil should be. 


Types of Cataracts

Symptoms and progression of a cataract will also depend on its type. These are the five main types:

The most common is called the nuclear cataract. These begin in the center of the lens and will gradually worsen over time. 

A baby can actually be born with cataracts in one or both eyes. These are called congenital cataracts and can vary in degree from very mild, barely affecting vision, to very severe. 

A rosette-shaped or petal-shaped cataract can form anywhere in the lens. These are called trauma-induced cataracts. 

Posterior subcapsular cataracts occur in the central back area of the lens. These tend to develop faster than the other types and are often associated with light sensitivity and a loss of color vision. 

A cortical cataract looks something like the spokes of a wheel, with the spokes growing inwards toward the center of the lens over time. These tend to cause a lot of glare and problems with night driving. 

Treatment of Cataracts

While cataract surgery is the only permanent way to fix a cataract, it may be possible to delay it for quite a while with other methods that still preserve good vision. 

Glasses, magnification glasses, strong bifocals, improved lighting, and other methods using various visual aids are some commonly used alternatives to surgery. When these methods begin to fail, your doctor will probably discuss cataract surgery with you. 

Cataract surgery involves removing the diseased natural lens and replacing it with an artificial one. The procedure is permanent. 

Poor vision as you age isn’t inevitable. Cataract surgery is typically highly successful and relatively painless. It’s the most commonly performed surgery in the United States.

How are Cataracts Diagnosed?

Your eye care professional may choose to diagnose your cataracts in several ways:

Retinal Exam

Before this exam, your doctor will place special drops in your eyes that cause the pupils to widen. This gives the physician a much better look at the inside of your eye and the retina and optic nerve at the back of the eye. 

This is also called a dilated eye exam and will reveal any cataract-like changes in the eye’s lens. 


Refraction is the part of the eye exam where your eye doctor determines what kind of vision correction you need to see with normal acuity. If your prescription has recently changed and you’re now unable to get the 20/20 vision with the correction you previously had, you may have a developing cataract. 

Slit Lamp Exam

The slit lamp is a device that kind of looks like a binocular microscope mounted to a table. Its powerful light source allows your doctor to examine your eyes at high magnification, revealing any possibly developing cataracts. 

Can you Prevent Cataracts?

For the most part, no. However, you can modify your lifestyle choices, such as smoking, exposure to the sun, and diet. For example, if you have diabetes, a known cataract risk factor, work with your doctor to keep your blood glucose within normal limits.

If you’re overweight, lose weight with a sensible diet and exercise plan approved by your doctor. Wear wraparound sunglasses rated for UVA and UVB light blocking. If you smoke, stop. It’s a risk factor for both cataracts and age-related macular degeneration, a serious retinal disease that can obliterate your central vision. 

Find a Top Eye Doctor Near You

Cataracts may have a genetic cause. If people in your family have them, it’s more likely that you will, too. This makes regular eye exams even more critical than ever. If you’re concerned about cataracts or any other eye problem or if you just need new glasses or contacts, we’re here to help.

Our professional staff is available to help you find a top-rated eye doctor in your area. During your confidential call, a trained staff member will answer any questions and help you set an appointment with one of our highly-trained eye doctors. 


Published on: Nov 11, 2021
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