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 happens when the 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.
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 have improved vision as a result.
Signs and Symptoms
- Decreased or blurred vision, often described as a "fog"
- Double vision
- Halo around lights
- "Second sight" -- when a person who normally wears reading glasses can suddenly read without them
- Brown spots in the visual field
What Causes It?
A cataract develops when protein in the lens clumps together and blocks light from reaching the retina. Researchers don't know what causes these proteins to clump together, but some think that cataracts may develop due to chemical changes in the lens that happen as people get older. 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 people with medical conditions (such as diabetes) or in those who use steroids
- Traumatic cataracts -- those that develop as a result of an eye injury
Who's Most At Risk?
The following factors may increase a person's risk for developing cataracts:
- Being older than 50
- Genetic diseases, such as Down syndrome
- Certain medications, such as steroids
- Having an infection such as rubella, taking drugs, or having radiation therapy during pregnancy
- Metabolic disorders, such as diabetes
- Eye disorders, such as glaucoma
- High-voltage electrical injury
- Gender -- women have a higher risk of developing cataracts than men
- Excessive exposure to sunlight
What to Expect at Your Provider's Office
People who have symptoms of cataracts should see an eye care professional. The eye care provider can make a diagnosis and help determine which treatment or treatments is right for them.
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
- Don't smoke
- Some medications may help delay cataracts from forming, particularly if you have diabetes or other high-risk conditions, but none can 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 people.
- Aldose reductase inhibitors may help prevent or delay cataracts in people with diabetes.
- Antibiotics and steroid eye drops may be prescribed after cataract surgery.
Surgical and Other Procedures
In its early stages, a cataract usually does not cause vision loss. 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. During surgery, the cloudy lens is replaced with a substitute lens.
Your doctor may also recommend having cataract surgery if you have other eye conditions, if the cataract threatens to cause another eye disorder, or if the cataract prevents examination or treatment of another eye problem.
Complementary and Alternative Therapies
A comprehensive treatment plan for cataracts may include a range of complementary and alternative therapies.
Nutrition and Supplements
While there are no supplements that will improve cataracts once you have them, eating more antioxidant-rich foods may help you maintain good eye health. Try green, leafy vegetables and peppers and berries, such as blueberries, cherries, and raspberries. Berries contain high levels of beneficial antioxidants for eye health.
Eating fish may help prevent cataracts. In one study, researchers found that women who ate fish 3 times a week rather than once a month had an 11% reduction in cataracts.
There has been some study of antioxidants in the diet, too. In a clinical study, 35,551 women who did not have cataracts gave researchers detailed information on their antioxidant nutrient intake from food and supplements. During the study, 2,031 cases of cataracts were confirmed over an average of 10 years of follow-up. The study suggested that higher dietary intakes of lutein and vitamin E from food and supplements significantly reduced the risk of cataract. However, there's no proof that taking these nutrients as a supplement will help. Lutein is found in green vegetables, egg yolks, squash, corn, grapes, and orange juice.
In another study, people who ate more foods with protein, niacin, thiamin, riboflavin, and vitamin A had fewer cataracts than those who ate less of these nutrients. Niacin, thiamin, and riboflavin are B vitamins. Again, the study looked at people who got the nutrients through food. Researchers don't know whether taking any of these vitamins as a supplement would help reduce the risk of cataracts.
The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, you should take herbs with care, under the supervision of a health care practitioner.
You may use herbs as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, make teas with 1 tsp. herb per cup of hot water. Steep covered 5 - 10 minutes for leaf or flowers, and 10 - 20 minutes for roots. Drink 2 - 4 cups per day. You may use tinctures alone or in combination as noted.
Bilberry (Vaccinium myrtillus) standardized extract, 80 mg 2 - 3 times daily, is an antioxidant that has been used traditionally to reduce the risk of cataracts. However, more studies are needed to see whether it is safe and effective. Bilberry may increase the risk of bleeding, especially if you take blood-thinners such as warfarin (Coumadin), clopidogrel (Plavix), or aspirin. Bilberry may lower blood sugar, so people who take diabetes medications should ask their doctor before taking bilberry. People with low blood pressure, heart disease, or blood clots should not take bilberry. Do not take bilberry if you are pregnant or breastfeeding.
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 -- your physical, emotional, and psychological makeup. An experienced homeopath assesses all of these factors when determining the most appropriate treatment for each individual.
The National Eye Institute estimates that about 90% of people who have cataract surgery have better vision afterward. 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 health care provider may prescribe eye drops or medications to help healing and control the pressure inside the eye for a few days following surgery. You may need to wear an eye shield or eyeglasses. A health care provider will schedule eye exams as needed to check on progress.
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- Last Reviewed on 09/29/2011
- Steven D. Ehrlich, NMD, Solutions Acupuncture, a private practice specializing in complementary and alternative medicine, Phoenix, AZ. Review provided by VeriMed Healthcare Network.
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This page was last updated: June 24, 2013