Vitamin C may ward off more than colds – study shows diet may reduce cataract risk by one-third

A new study published March 23 in the journal Opthalmology suggests vitamin C may ward off more than colds. Researchers found that a diet rich in the nutrient can reduce the risk of cataract progression by one-third, whether it was consumed through food or a supplement. The study is the first to show that genetics may not be as important as diet in the development of cataracts.

Cataracts occur naturally with age, causing the lens of the eye to become cloudy. Although they can be removed, they are the leading cause of blindness throughout the world. According to the research, a person’s genetics accounts for about 35 percent of the risk for cataracts, with diet and environmental factors making up the other 65 percent.

Vitamin C is an antioxidant, which the research team says may explain how it can reduce the risk of developing cataracts. Oxidation can cause the lens of the eye to cloud. Since the fluid inside the eye relies on a high level of vitamin C to prevent that oxidation, a vitamin C-rich diet can provide extra protection.

Dr. Christopher Hammond, lead author of the study, said “While we cannot totally avoid developing cataracts, we may be able to delay their onset and keep them from worsening significantly by eating a diet rich in vitamin C.”

The study, performed at King’s College London, looked at more than 1,000 pairs of female twins from the UK. A food questionnaire was used to track vitamin C intake, along with other nutrients. Digital imaging was used to check the lens’ opacity at about age 60, with a follow-up measure 10 years later on 324 pairs of the twins. Baseline measurements showed a 20 percent cataract reduction risk with a diet rich in vitamin C. Ten years later that figure had increased to 33 percent for the women who reported consuming more vitamin C-rich foods.

Hammond cautions that the study shows only associations and cannot prove a cause-and-effect relationship between cataracts and vitamin C. However, he says “the most important finding was that vitamin C intake from food seemed to protect against cataract progression.”