Vitamin C may promote age-related cataract in women

Women who use high doses of vitamin C supplements may be at higher risk of age-related cataract, according to a new study in the Nov 18, 2009 issue of American Journal of Clinical Nutrition.

Women who used vitamin C supplements were 25 percent more likely than those who did not use to experience cataract exaction, the study found.

Early animal studies have shown adverse effects of high doses of vitamin C supplements on age-related cataract.

For the study, Rautiainen S and colleagues from Karolinska Institutet, Stockholm, Sweden and other organizations followed 24,593 women aged 49 to 83 who participated in the Swedish Mammography Cohort between September 1997 and October 2005.

The participants were surveyed for their lifestyle via a self-administered questionnaire and incidence of cataract in the study population was recorded. During the 8.2-year follow-up, 2497 cataract extraction cases were identified.

Women who used vitamin C supplements for more than 10 years were 46 percent more likely than nonusers to have cataract extraction.

Compared with women who did not use vitamin C, The risk was increased by 56 percent in women who used both hormone replacement therapy and vitamin C supplements and increased by 97 percent in those who used supplements and corticosteroid.

The researchers conclude "Our results indicate that the use of vitamin C supplements may be associated with higher risk of age-related cataract among women."

Vitamin C is found high in fruit and vegetables. It has been known for many health benefits.



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