High-GI diet may cause cataracts

Last updated: Monday, December 03, 2007 Print

People who eat lots of high glycaemic index foods may be increasing their risk of developing a cataract, a clouding of the lens of the eye, according to research reported in the American Journal of Clinical Nutrition.

Glycaemic index, or GI, refers to how rapidly a food causes blood sugar to rise. High-GI foods, like white bread and potatoes, tend to spur a quick surge in blood sugar, while low-GI foods, such as lentils, soybeans, yoghurt and many high-fibre grains, create a more gradual increase in blood sugar.

The quantity and quality of carbohydrates in the diet may play a role in cataract formation, Dr Paul Mitchell, from Westmead Hospital, New South Wales, and colleagues note in their report.

The researchers examined the association between dietary carbohydrates and the occurrence of cataracts in 933 people who were at least 49 years of age at the outset and were followed for up to 10 years.

What the study showed
After accounting for age, gender, diabetes and other factors that might influence the results, each standard deviation increase in dietary GI was associated with a 19 percent increase in the risk of developing cataracts.

People with the highest GI diets were 77 percent more likely to develop a cataract than people with the lowest GI diets.

"Because carbohydrate foods represent the main dietary component for humans and cataract entails such a significant health and economic burden, further studies to clarify whether aspects of dietary carbohydrate intake may affect the risk of cataract development are warranted," Mitchell and his associates conclude. – (Reuters Health)