Incidence of cataracts affected by the use of multivitamins

By Dr Ira Bernstein - 

A new study has just been published as part of the Physicians Health Study II looking at the effect of a daily multivitamin (Centrum Silver) and how it affects the incidence of cataracts and age related macular degeneration (AMD). This study which I have written about before, involved almost 15000 middle age and older older U.S. male physicians followed for an average of 11.2 years.

In this large-scale randomized trial long-term daily multivitamin use modestly and significantly reduced the co-primary vision end point of cataract after more than 10 years of treatment and follow-up. There was no significant benefit or risk of daily multivitamin use on visually significant age related macular degeneration.

It should be noted that the multivitamin in this study contained nutrients only at RDA levels (low dose) ---Zinc 15 mg; Vitamin E 45 IU (synthetic form); vitamin C 60 mg; beta carotene (5000 IU vitamin A 20% as beta carotene]. Other studies containing higher doses of vitamins have demonstrated benefit in reducing age related macular degeneration. The authors of this study postulate that it may be that the low dosage of the nutrients in this Centrum study may be the reason that no benefit was seen with respect to AMD.

I would hypothesize that comprehensive multivitamin and mineral supplementation in OPTIMAL amounts, not RDA levels would not only reduce cataract formation but also AMD. It is logical, just not proven in large clinical trials.