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Are cataracts just another consequence of getting old? This may appear to be the case, since they’re quite common in older Canadians. It has even been suggested that if we live long enough, most of us will develop a cataract. However, there are nutritional and lifestyle choices that can prevent, stop and even reverse the progress of early-stage cataracts.

What are cataracts? They are opaque areas on the lens of the eye, a flexible structure composed of protein and water. Cataracts occur when the protein structure is damaged and coagulates, much the way that egg white becomes opaque when cooked. As the opacity thickens and the lens becomes less flexible, more and more light is prevented from passing through the lens and reaching the retina.

There are three types of cataract, characterized by the location on the lens. The most common type, the nuclear cataract, occurs in the centre of the lens and is associated with aging. The cortical cataract begins as spoke-shaped opacities that extend from the outside of the lens to the centre. (People with diabetes may develop this type.) A subcapsular cataract usually begins at the back of the lens as a small opacity under the outer membrane of the lens; this type is often found in people with diabetes or those on steroids.

Cataracts are the leading cause of blindness and tend to develop gradually and painlessly over a period of many years. At first you may think you simply need stronger glasses or you may begin to complain about glare. As the lens of the eye continues to change, your vision may become cloudy or blurred, as if you are looking through frosted glass. Ironically, there can be a temporary improvement in your reading vision, but this disappears as the cataract worsens. You may see halos around lights or find that you need brighter light to read by. Colours may seem faded and your depth perception may change.

Cataract Symptoms

If you have symptoms, it is important to have a comprehensive eye examination. The primary cause is oxidative damage. The longer you live, the more exposure you have to free radicals from such sources as pollution. Other factors that lead to oxidative damage and can contribute to the formation of cataracts include:

• smoking


• high blood sugar levels in people with uncontrolled diabetes


• excessive alcohol consumption


• long-term use of certain medications such as steroids, antibiotics, antihistamines and aspirin


• a previous eye injury


• poisoning by chemical substances


• nutritional deficiencies, especially of antioxidants


• over-exposure to sunlight from beaches, snowfields and time in tropical locations.

Nutritional Protection

People with a high dietary intake of antioxidants have a lower risk of developing cataracts. Antioxidants, such as vitamins C and E and beta-carotene, counteract the destruction caused by free radicals. Vitamin C is particularly important for the eye and its concentration in the fluid in front of the lens is among the highest of all body fluids. Some studies indicate that vitamin C supplementation in the early stages can reverse cataract formation. Vitamin C is found in all fruits and vegetables and is particularly high in bell peppers, parsley, broccoli, strawberries and citrus fruits.

Carrots truly are good for the eyes! They contain beta-carotene, a plant pigment that offers antioxidant protection. Other carotenoids are found in all the richly coloured dark green and yellow-orange fruit and vegetables. Lutein is particularly valuable to the eyes and is available in dark green, leafy vegetables such as kale, spinach and collards. Research has shown that spinach may offer better protection from cataracts than any other food. Blueberries have been known for a long time to be beneficial to eyesight because they contain anthocyanidin, a bioflavonoid that is especially helpful in protecting the lens of the eye.

White sugar and refined flour create blood sugar problems and should be avoided. Margarine and other processed vegetable oils promote the formation of harmful free radicals. Your daily diet should consist of 10 servings of vegetables and fruit, balanced with legumes, whole grains, nuts and seeds, omega-3 oil from flax seeds and protein and fat from eggs, nuts, seeds and whole, cultured dairy products.

Look Ahead with Prevention

The following steps can help you prevent the development of cataracts:

• do not smoke


• some sun is necessary and healthy, but protect yourself from too much sun in the middle of the day. Wear a wide-brimmed hat in direct sun and sunglasses that offer good protection from the glare.


• vitamin C: 500-1,000 mg three times daily


• beta-carotene: 10,000 IU per day


• vitamin E (mixed tocopherols): 400 IU per day


• quercetin (especially for cataracts in diabetics): 500 mg twice daily


• alpha lipoic acid (an antioxidant that is both fat- and water-soluble): 100 mg daily


• bilberry (Vaccinium myrtillus) (25 per cent anthocyanidin content): 40-80 mg three times daily

Cataract Surgery Risks

Cataract surgery is the most commonly performed treatment for this condition. Although approximately 95 percent of surgeries go off without a hitch, this operation should never be trivialized. A patient should be aware of the following risks.

Endopthalmitis–otherwise known as interocular infection. Precautions are generally taken pre- and post-operation, but this does occur in one out of every 3,000 cases. Watch out for excessive eye redness, pain, light sensitivity and worsening vision.

Cystoid macular edema–inflammation after surgery can cause the retinal blood vessels to leak fluid causing decreased central vision.

Retinal detachment–this occurs when liquid gets into the surgery site through a fine tear in the retina allowing it to separate abnormally from the back wall of the eye. A retinal separation may cause a “curtain” effect over part of the vision. Other symptoms include flashes of light (similar to lightning).

Dislocated lens material–in some instances, lens material can fall back into the cavity of the eye. Often small pieces of this dislocated material can cause inflammation and pain. A second surgery is sometimes necessary.

Chordial hemorrhage–sometimes during surgery acute bleeding can occur in the delicate pattern of blood vessels underneath the retina. This is most common among elderly patients. Bleeding can usually be localized and easily treated. Other times it can be more severe and substantial vision loss follows.

Andrea Lemieux is a registered nutritional consultant in private practice in Toronto, ON.

Source: alive #229, November 2001