Daily Multivitamin Might Curb Cataracts

Multivitamin supplements decreased cataract risk but not macular degeneration risk

(RxWiki News) Vitamin supplements may help people get nutrients that their diet lacks or they can't absorb. It seems that supplements may also reduce the risk of developing at least one eye condition.

Both cataracts and macular degeneration are conditions more common in older people. In age-related macular degeneration, damage to the retina causes loss of vision that starts in the middle of the field of vision. Cataracts cloud the lens of the eye and decrease vision.

Using data from a large study of physicians who took regular vitamin supplements, a research team looked at future occurrence of cataracts and macular degeneration.

These researchers found that vitamin supplements decreased the risk of developing cataracts, but did not change the risk of developing macular degeneration.

"Talk to your doctor before taking vitamin supplements."

William G. Christen, ScD, from the Department of Medicine at Brigham and Women’s Hospital and Harvard Medical School in Boston, MA, and a team of researchers conducted this study.

Participants for the study came from the Physicians Health Study II, which recruited doctors into the research from 1997 to 1999. The study recruited 14,641 male doctors, age 50 and over, who were split into two treatment groups.

One group of 7,317 men took a Centrum Silver multivitamin and 500 mg vitamin C daily and 400 IU of vitamin E and 50 mg beta-carotene every other day. The other group of 7,324 men took a placebo (fake multivitamin and supplements).

The research team evaluated the participants for over an average of 11 years by having the doctors complete questionnaires about whether they had been diagnosed with cataracts or macular degeneration.

The results of the research showed 872 cataract cases in the multivitamin group and 945 cases in the placebo group. That corresponded to a 9 percent lower risk of cataracts in the multivitamin group compared to the placebo group.

At age 70 and older, the cataract risk was 15 percent lower in the multivitamin group than in the placebo group.

Differences in the risk of macular degeneration between the multivitamin group and the placebo group were not statistically significant.

The researchers cited some limitations of their study. Some of the nutrients in the multivitamin used for this research were changed by the manufacturer during the study. The study included only male doctors who were well nourished, and the study team noted that their findings may not apply to women or to people who are less well nourished.

“In conclusion, the finding in this large-scale randomized trial of middle-aged and older men that long-term daily multivitamin use is associated with a modest but significant reduction in cataract ... is consistent with results of previous trials of multivitamin use in cataract prevention,” the authors wrote.

This study was published in the February issue of Ophthalmology.

The researchers disclosed potential conflicts of interest with a number of institutions and companies, the National Institutes of Health, DSM Nutritional Products Inc. (formerly Roche Vitamins), Bristol-Meyers Squibb, AstraZeneca, Novartis and Merck, among others.

Review Date: 
February 25, 2014