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SYDNEY, AUSTRALIA. Several studies have found that vitamin C and vitamin E delay the development of
cataracts. Now researchers at the University of Sydney report that supplementing with multivitamins
especially vitamin A and vitamin B complex also have a protective effect. Their study involved 2873 men
and women between the ages of 49 and 97 years who had completed food frequency questionnaires
including type, dose, and duration of supplement usage. The researchers checked each participant for the
presence of cataracts (cortical, nuclear or posterior subcapsular) using lens photography and a standard
grading procedure.
After adjusting for age, gender, hypertension, diabetes, smoking, sun exposure, education, and use of
steroids the researchers conclude that vitamin A and certain B vitamins lower the risk of nuclear and cortical
cataract development substantially. Thiamin (vitamin B1) was found to lower the risk of nuclear cataract by
40 per cent and the risk of cortical cataract by 30 per cent in doses greater than 4.4 mg/day. Folic acid and
vitamin B12 were found to be strongly protective against both cortical and nuclear cataracts (40-70 per cent
risk reduction). Vitamin A was found to be highly protective against nuclear cataract particularly if taken in
doses of 3000 micrograms/day (15,000 IU) or greater (risk reduction of 90 per cent). Riboflavin (vitamin B2)
and, to a lesser extent, niacin (vitamin B3) were also found to be somewhat protective against cortical
cataract.
The researchers conclude that dietary vitamin supplement use is associated with a reduced incidence of
both nuclear and cortical cataract and could delay their onset.
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