Your Diet Can Help Fight Against Cataract

Read an interview with Allen Taylor, PhD, World-Renowned Vision Researcher on Nutrition, Cataract and AMD

What Causes Cataract

The eye's lens functions like the lens of a camera, focusing light on the back of the eye to produce sharp. The lens is made up mostly of water and protein fibers. Over time, the protein fibers begin to clump together. When the protein clumps up, it clouds the normally clear lens. And when the clouded area gets large enough, it can be like trying to see through a frosty window.

Certain diseases like diabetes, eye injury or family history can increase the risk of cataract, but long-term damage caused by free radicals is believed to be a big contributor to most age-related cataracts. Excessive exposure to sunlight and smoking are major sources of free radicals. So wearing UV-protective lenses when you're outside and not smoking are two things you can do to help protect against free radicals. Keeping up your antioxidant defenses is another sound strategy.

Antioxidants and Cataract

According to Dr. Allen Taylor of Tufts University Nutrition and Vision Laboratory, the totality of the available evidence suggests that antioxidants have benefit in the long term for reducing cataract risk. "Since early cataract probably begins at about age 45, people in their 30's and 40's should be eating more fruits and vegetables to improve their antioxidant intake." There are a number of nutrients in fruits, veggies and other healthy foods that may impact the risk for cataract development:

Vitamin C

A number of observational studies have linked increased dietary intake or blood levels of vitamin C with decreased risk of cataracts. A study from Tufts and Harvard reports that women consuming the highest levels of vitamin C had about a 60% lower risk of developing cortical cataract than those with the lowest intake levels. Additionally, women who took vitamin C supplements for 10 years or more had a similar reduction in risk for nuclear cataract (clouding of the central portion of the lens) (1). Those studies that have found a relationship between C and cataracts, suggest that intake may have to be higher than 300 mg/day for years before a protective effect can be detected.

Lutein andzeaxanthin

The large Nurses Health Study showed a reduced likelihood of cataract surgery with increasing intakes of lutein and zeaxanthin (2). Similarly, the Health Professionals Follow-Up Study reported a trend toward lower risk of cataract surgery in men consuming more of these carotenoids from green leafy vegetables (3).

vitamin E

Results of a new study from Tufts suggest that long-term use of vitamin E supplements as well as higher riboflavin and/or thiamin intake may reduce the progression of age-related cataract (4). Since few people eat the recommended 5 daily servings of fruits & veggies or consume high amounts of vitamin E, supplements can help close the dietary gap for vitamins C and E and lutein.

Fish and Red Wine

Recent studies have also linked drinking moderate amounts of red wine, and a higher intake of long-chain omega-3 fatty acids from fish with risk reduction for cataract (5,6). More research is needed before we can definitely add them to the cataract-protective list. But you don't have to wait for more evidence to enjoy them since we already know that they're good for the heart and circulatory system.

References

1. Jacques PF et al. Long-term nutrient intake and early age-related nuclear lens opacities. Archives of Ophthalmology 119:1099-19, 2001.
2. Chasen-Taber et al. A prospective study of carotenoid and vitamin A intakes and risk of cataract extraction in US women. American Journal of Clinical Nutrition 70:509-516, 1999.
3. Brown et al. A prospective study of carotenoid intake and risk of cataract extraction in US men. American Journal of Clinical Nutrition 70:517-524, 1999.
4. Jacques PF et al. Long-term nutrient intake and 5-year change in nuclear lens opacities in women. Arch Ophthalmol 123:517-26, 2005.
5. Lu M et al. Prospective study of dietary fat and risk of cataract extraction among U.S. women. Am J Epidemiol 15:161:948-59, 2005.
6. Jonasson F et al. Abstract B198, ARVO Annual Meeting, May 4, 2005.