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.

• Decreased or blurred vision (often described as a "fog") 
• Double vision 
• Halo around lights 
• "Second sight" -- when an individual who normally wears reading glasses can suddenly read without them 
• Brown spots in the visual field 

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:

• Age-related cataracts—those that develop with older age 
• Congenital cataracts—those that are present at birth or develop in early childhood, usually in both eyes 
• Secondary cataracts—those that develop in individuals with medical conditions (such as diabetes) or in those who use steroids 
• Traumatic cataracts—those that develop as a result of an eye injury 

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

• Being older than 50 years of age
• Genetic diseases (such as Down syndrome) 
• Certain medications (such as steroids) 
• Maternal infection (such as rubella), drug ingestion, or radiation therapy during pregnancy 
• Metabolic disorders (such as diabetes mellitus) 
• Eye disorders (such as glaucoma) 
• High-voltage electrical injury 

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:

• Visual acuity test—measures vision at various distances 
• Pupil dilation—the pupil is widened with eye drops to reveal more of the lens and retina 
• Tonometry—measures fluid pressure inside the eye 

• Wear ultraviolet (UV)-blocking sunglasses 
• Abstain from smoking cigarettes

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.

• Eye drops (containing phenylephrine and homatropine) may be prescribed to dilate the pupil and provide better vision in some individuals
• Aldose reductase inhibitors may help prevent or delay cataract formation in people with diabetes 
• Antibiotics and steroid eye drops may be prescribed following the removal of cataracts 

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.

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

• Antioxidants may protect the lens against damage caused by free radicals. Dark leafy greens, orange and yellow vegetables, vitamins A and C, and beta-carotene are good sources of antioxidants. Dark berries, particularly blueberries, may also help protect the lens. 
• Glutathionine supplements may protect against UV light; selenium supplements also help keep glutathionine in its active form 
• Vitamin E may also protect the lens against free radical damage.

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:

• Dusty miller (Cineraria maritima) succus (preserved plant juice); may cause eye irritation 
• Bilberry (Vaccinium myrtillus) 
• Ginkgo (Ginkgo biloba) 

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.

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.

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.

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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