Age-related cataracts are the leading cause of low vision and blindness throughout the world. Up to 30% of people over the age of 50 will develop them. By age 75, about 70% will have cataracts. Surgery to remove cataracts has become almost routine.
Cataracts develop when proteins build up in the lens of the eye making it cloudy. It happens with age and is primarily due to
oxidative damage. Age-related cataracts are the result of a lifetime of molecular damage to the lens proteins by free radicals.
Can your diet make a difference? Studies to date haven't been conclusive. Animal studies have found that wheat grass reverses cataract damage. Human studies have found only a non-significant or modest association between fruit and vegetable intake and cataract risk.
But the most recent study from Spanish researchers is more promising. An article published online onBMC Ophthalmology , finds a significant relationship between high intakes of fruits and vegetables and lowered risk of cataracts. In addition, taking in more vitamins C and E is also associated with fewer cataracts.
High Intake of Fruits and Vegetables Lowers Cataract Risk
The researchers analyzed data from the Spanish segment of the European Eye study (EUREYE) collected between February 2000 and November 2001. The subjects included 599 adults age 65 or older. Participants completed a food frequency questionnaire to assess how many fruits and vegetables they typically ate. The researchers also measured blood plasma levels of vitamin C, alpha-tocopherol (vitamin E), and various carotenoids. Of the participants, 50% ate five or more servings of fruits and/or vegetables a day. That number is high compared to what Americans eat. The researchers noted that the general population of Spain eats a Mediterranean diet rich in fruits and vegetables, especially citrus fruit. The researchers showed that the more combined fruits and vegetables the participants ate, the lower their cataract risk. The same was true of vitamin C.
Vitamins C and E Associated With Lower Cataract Risk
As vitamin C intake increased above 107 mg per day, the risk of developing cataracts significantly decreased. One orange has about 70 mg of vitamin C. And the more vitamin C people ate – up to a point - the lower the risk.
Compared to those eating the least fruits and vegetables a day (between 13 mg to 83 mg), those eating up to 107 mg lowered their risk by 38%. Those eating up to 143 mg per day lowered their risk by 51%. However, those eating up to 408 mg every day didn't see much more improvement. They lowered their risk by 54%. The researchers noted this was consistent with other research finding human eye tissues become saturated at intakes of vitamin C between 200 and 300 mg per day.
Vitamin E intake above 8 mg per day showed a protective association against developing cataract. An ounce of sunflower seeds contains about 10 mg of vitamin E. But there was no evidence that more vitamin E contributed to additional decreases in risk.
The researchers also measured the effects of other dietary antioxidants including lutein, zeaxanthin, β-cryptoxanthin, α-carotene, β-carotene, and lycopene. But none of those antioxidants were associated with cataract risk. The researchers admitted this result was not consistent with other epidemiological studies and called for more research.
Until then we know that high daily intakes of combined fruit and vegetables, as well as vitamins C and E are associated with a significantly decreased risk of cataract.
What does this mean for you?
Foods To Protect Against Cataracts
The researchers observed that high intakes of fruit alone did not significantly lower cataract risk. But vegetables alone did make a significant difference.
To keep your eyes healthy, eat vegetables rich in vitamins C or E. Broccoli is high in both of those vitamins.
Vegetables high in vitamin C include kale, bell peppers, Brussels sprouts, cauliflower, tomatoes, and snow peas. Foods high in vitamin E include spinach, avocados, sunflower seeds, squash, and pumpkin.