Cataracts are clumps of protein that collect on the lens of an eye and interfere with vision. Normally, light passes through the lens (the clear tissue behind the pupil) and focuses on the retina. The retina is the light-sensitive layer of the eye that sends visual signals to the brain. A cataract occurs when the normally clear lens becomes cloudy. Most cataracts develop slowly over time and are a natural result of aging. Once cataracts become large enough that vision loss interferes with everyday activities such as driving, reading, or watching television, they should be surgically removed.

Signs and Symptoms

What Causes It?

A cataract develops when protein in the lens clumps together and blocks light from reaching the retina. It is not clear what causes these proteins to clump together, but some researchers speculate that cataracts may develop as a result of chemical changes in the lens that occur with aging. Other researchers believe that there may be several causes of cataracts including smoking, diabetes, and excessive exposure to sunlight.

There are several different types of cataracts:

Who's Most At Risk?

The following factors may increase an individual's risk for developing cataracts:

What to Expect at Your Provider's Office

Individuals experiencing symptoms associated with cataracts should see an eye care professional. He or she can make a diagnosis and help determine which treatment or combination of therapies is most appropriate.

Eye care professionals can detect cataracts with the following tests:

Treatment Options


Certain medications may help delay cataract formation (particularly in those with diabetes or other high-risk conditions), but none are known to reverse the progression of cataracts once they form.

Drug Therapies

Surgical and Other Procedures

In its early stages, a cataract usually does not interfere with vision. Over time, however, a cataract may grow larger and cloud over more of the lens, making it difficult to see. When cataracts cause vision loss that interferes with everyday activities such as driving, reading, or watching television, surgery is the only effective treatment. An eye care professional may also recommend that an individual remove a cataract if he or she has other eye conditions, if the cataract threatens to cause another eye disorder, or if the presence of the cataract prevents examination or treatment of another eye problem. During surgery, the cloudy lens is replaced with a substitute lens. Cataract removal is one of the most common operations performed in the United States today. According to the National Eye Institute, roughly 90% of people who have cataract surgery experience improved vision as a result.

Complementary and Alternative Therapies

A comprehensive treatment plan for cataracts may include a range of complementary and alternative therapies.

Nutrition Herbs
The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and that can interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, preferably under the supervision of a practitioner knowledgeable in the field of botanical medicine. A healthcare practitioner may recommend the following herbs for the treatment of cataracts: Homeopathy
Although very few studies have examined the effectiveness of specific homeopathic therapies, professional homeopaths may consider certain remedies for the treatment of cataracts based on their knowledge and experience. Before prescribing a remedy, homeopaths take into account a person's constitutional type. A constitutional type is defined as a person's physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.

Physical Medicine
Contrast hydrotherapy (alternating hot and cold water applications to the face or back of neck) may improve circulation to the head and facilitate the transport of nutrients to the eye.

Prognosis/Possible Complications

The National Eye Institute estimates that approximately 90% of individuals who have cataract surgery experience improved vision as a result. Complications from surgery are rare, but can include infection, bleeding, retinal detachment, inflammation (pain, redness, swelling), loss of vision, or light flashes. With prompt medical attention, such problems can usually be treated successfully.

Following Up

A healthcare practitioner may prescribe eye drops or medications to help healing and control the pressure inside the eye for a few days following surgery. An eye shield or eyeglasses may also be necessary. A health care provider will schedule eye exams as needed to check on progress.


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