Our grandparents used to say that eating a lot of carrots is necessary to have good eyesight. But today, research goes a step further by saying that eating foods rich in vitamin C can slow the progression of cataracts, a condition we cannot «escape» due to the natural aging of the eyes. Unfortunately, even in this day and age, cataracts can lead to complete loss of vision.
Researchers at King's college London followed the progression of cataracts (the progressive clouding of the crystalline lens of the eye) in 324 eyes of twin women in the UK. They examined photographs of the patients' lenses to determine the stage of disease progression. At the same time the participants were given a questionnaire relating to their nutrient intake, including vitamin C.
Although, as mentioned, cataracts are considered an ’eye condition« due to ageing, researchers have found that environmental factors, such as diet, can have a protective-preventive effect. At the beginning of the study, people who ate a diet rich in vitamin C had a reduced risk of cataracts. After 10 years, participants who consumed more vitamin C had a 33% risk reduction in cataract progression, compared to people who consumed less.
Researchers hypothesize that consuming vitamin C may increase the levels of the existing vitamin in the eye fluid, forming a protective barrier against cataracts.
Study leader Dr Chris Hammond said in a press release issued by the American Academy of Ophthalmology that it is not possible to stop ageing, but it is possible within the context of a healthy and balanced diet and lifestyle - including regulating blood sugar and stopping smoking - to reduce the likelihood of cataract surgery.
The US dietary guidelines recommend that American adults consume 65-90mg of vitamin C per day, with a maximum of 2000mg. This upper limit was set as excessive daily intake of vitamin C can cause diarrhea or even nausea. The National Institutes of Health suggests that most of the vitamin C should be consumed from foods such as peppers, dark green leafy vegetables, kiwi, broccoli, berries, citrus fruits, tomatoes, peas and papaya.
