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Ears, Nose, Throat and Health

Cataracts, vitamins help

WILL VITAMIN C AND E HELP TO PREVENT CATARACTS?

By Dr. W. Gifford Jones

April 6, 1991

The figures are staggering. 541,000 cataract extractions are performed annually in the U.S. Among Americans between the age of 60 and 75, 20 per cent have visually disabling cataracts. Cataracts are the leading cause of impaired vision and blindness in the elderly and they affect 400,000 people every year. The cost of treating cataracts is also soaring. Last year 3.5 billion dollars was spent in the U.S. removing these clouded lenses. What causes the lens of the eye to become foggy? And how do vitamins C and E act to help fight this disabling disease?

Diabetics have four times the chance of developing opacities in the lens. Patients suffering from hypothyroidism, and glaucoma also have a higher incidence of cataracts. Exposure to radiation, high electric voltage or being struck by lightning may instigate this problem. And if your Father and Grandfather both suffered from cataracts at the age of 45, it's highly likely you will experience the same trouble.

The majority of cataracts are caused by aging. Early symptoms are inconspicuous. Colours begin to appear a trifle dull with less contrast. Later, as opacity increases, patients are bothered by increased glare, making night driving tedious due to the brightness of oncoming lights. And they certainly need help when road signs can no longer be read.

Professor Paul Jacques, of The Human Nutrition Research Centre on Aging at Tufts University, Boston, says evidence suggests that cataracts are caused by the oxidation of lens protein. During the normal metabolic process oxidation produces what are known as "free radicles". These highly reactive molecules damage the cells in the lens just as oxygen causes paper to turn yellow or butter rancid. Vitamin C and E are antioxidant vitamins which act as scavengers to help "mop up", deactivate or destroy free radicles or prevent their formation.

Professor Jacques studied the dietary intake and blood levels of vitamin C and E in 112 subjects. 77 of them had one or more cataracts and 35 were cataract free. Comparison of the two groups found that people with low blood levels of vitamin C were 11 times more likely to develop a cataract.

Professor Shambhu Varma, of the University of Maryland, says the formation of cataracts involves many factors. But that vitamin C is a protective agent. The cornea, lens and aqueous humour of the eye have one of the highest concentrations of vitamin C in the body.

Dr. James Robertson of the University of Western Ontario compared the intake of antioxidant vitamins by 175 cataract patients and a similar number of cataract-free individuals over a five year period. He found that the cataract-free group took significantly more vitamin E than the cataract patients. He reported that those who took vitamin E supplements had reduced cataract risk by 50 to 70 per cent.

Robertson's colleague, Dr. John Trevithick, studied the effect of vitamin E on diabetic rats who are especially prone to cataracts. He reports that vitamin E supplements decreased the leakage of lens protein into fluids surrounding the eye, one indication of cataract formation.

Eyes, like the rest of the body, eventually age. There's also no conclusive evidence that antioxidant vitamins will prevent cataract formation. But there is reason to believe that they may slow down their formation.

What should we all do? It makes economic and medical sense to try and slow down cataract formation. For example, 46 per cent of North Americans between ages 75 to 78 have senile cataracts. Delaying the growth of cataracts by 10 years would reduce the number of cataract operations by half.

Clearly, the message is to eat fruit and vegetables. Professor Jacques found increased risk of cataract in patients with poor diets. Those who consumed less than 3.5 servings of fruit or vegetables a day showed a 13 times greater increase in the risk of cataract.

Debate continues about whether supplemental vitamins should be taken and if so, how much. The majority of Dr. Robertson's subjects took supplements containing between 300 to 600 milligrams of vitamin C and 400 International Units of vitamin E.

Medical consumers should also be prudent in protecting their eyes from long exposure to strong sunlight. This causes the production of oxygen deprived free radicles. And as a result of this the incidence of cataracts increases closer to the equator. Increasing altitude is also associated with increased cataract formation. For instance, the people in Tibet suffer one of the highest rates of cataract incidence in the world.

One last cautionary note. Year after year too many people of all ages develop traumatic cataracts or lose an eye needlessly. Some fail to use face protectors during games such as hockey. Or protective glasses while playing squash or tennis. Don't let this happen to you or one of your family.


W. Gifford-Jones M.D is the pen name of Dr. Ken Walker graduate of Harvard. Dr. Walker's website is: Docgiff.com

My book, �90 + How I Got There� can be obtained by sending $19.95 to:

Giff Holdings, 525 Balliol St, Unit # 6,Toronto, Ontario, M4S 1E1

Pre-2008 articles by Gifford Jones
Canada Free Press, CFP Editor Judi McLeod