Taking Vitamin C Supplements Increases Risk of Cataracts

Vitamin C is an antioxidant vitamin that’s important for immune function, wound healing, and producing collagen – the protein that keeps skin and joints healthy. Eating vitamin C rich food with meals also helps the body absorb more iron. Some people assume that because vitamin C plays an important role in health – more must be better – so they take supplemental vitamin C. While there’s little danger of getting too much vitamin C through diet, taking large vitamin C doses in pill form isn’t necessarily beneficial and may even carry some risks. A new study shows that taking vitamin C supplements could increase the risk of cataracts.

Supplemental Vitamin C and Cataracts

Cataracts are a disease where the lens of the eye gradually grows cloudy over time until eyesight is impaired. Certain diseases such as diabetes and high blood pressure increase the risk of cataracts – as does exposure to radiation and ultraviolet light. Cataracts are one of the leading causes of blindness worldwide – especially in areas where surgery isn’t available to correct the problem.

Vitamin C and the Risk of Cataracts: A Study

In a study published in the American Journal of Clinical Nutrition, researchers looked at the records of 24,593 women age 49 and older. After following the women for over eight years, they found that women who took supplemental vitamin C were thirty-eight percent more likely to develop cataracts than those who got their vitamin C naturally through diet.

Is Supplemental Vitamin C Harmful?

It’s difficult to know what to make of this study since some previous studies have shown that high vitamin C doses may actually reduce the risk of cataracts. It makes sense since vitamin C is an antioxidant vitamin and cataracts are thought to be related to oxidative stress to the lens of the eye.

Many experts recommend a diet rich in antioxidant vitamins such as vitamin C, vitamin E, and carotenoids to help reduce the risk of cataracts as well as another common vision robbing disease – macular degeneration of the eye. Why the discrepancy? Whether or not vitamin C increases or decreases the risk of cataracts could be dependent on how much is taken, the length of time it’s taken, and whether it comes from supplements or from a vitamin C rich diet.

The Bottom Line

This study certainly muddies the picture when it comes to vitamin C and the risk of cataracts. It does seem likely that antioxidants play a role in preventing cataracts, but the safest way to get them is through a diet rich in antioxidant vitamins rather than supplemental vitamin C. Experts believe that high vitamin C doses may actually have harmful pro-oxidant effects and high doses of vitamin C cause diarrhea in some people. Get your vitamin C the safe way – from oranges, kiwis fruit, and green peppers instead