How much of vitamin C rich foods do you take every day? Experts say that vitamin C may protect against cataract, a common cause of preventable blindness.
Experts found that simple dietary changes such as increased intake of fruit and vegetables such as strawberries, potatoes and oranges as part of a healthier diet could help protect from cataract.
Researchers looking at the progression of cataracts in 324 pairs of female twins over 10 years found that increasing vitamin C intake may have a protective effect against the progression of cataract.
Cataracts, which are a clouding of the clear lens part of the eye that helps focus light on the retina, are a common cause of blindness, especially in older people. It occurs in 45 per cent of people older than 75 years, and their removal is the most commonly performed surgical procedure among older people.
While sunlight is the major source of the lens damage that causes cataract, there is growing evidence that poor overall nutrition and chronic inflammation in other parts of the body damage the eyes.
In carrying out the study, photographs of the participant’s lenses showing the opacity of the lens in detail were examined. Participants intake of vitamin C was also measured using a food questionnaire.
They found that participants with high levels of dietary vitamin C had a 33 per cent reduction in their risk of cataract progression and ‘clearer’ lenses after 10 years than those who had consumed less dietary vitamin C.
The study’s authors in the journal, 2016 edition of Ophthalmology, believed that eye fluid that bathed the lens is high in vitamin C. This helps to stop the lens becoming cloudy.
They suggested that increased vitamin C intake exerted a preventative effect on cataract progression by increasing the vitamin C available in this fluid.
Professor Chris Hammond, consultant eye surgeon and lead author of the study from the Division of Diabetes and Nutritional Sciences at the university, said: “The findings of this study could have significant impact, particularly for the ageing population globally by suggesting that simple dietary changes such as increased intake of fruit and vegetables as part of a healthier diet could help protect them from cataracts.
“While we cannot avoid getting older, diabetes and smoking are also risk factors for this type of cataract, and so a healthy balanced diet and lifestyle generally should reduce the risk of needing a cataract operation.”
Previous studies such as the Age-Related Eye Disease Study and the Blue Mountains Eye Study had also shown vitamin C intake, through both diet and supplements, as protective against cataracts.
Similarly, a large-scale placebo-controlled trial, published in Ophthalmology also suggested that long-term supplementation with a multivitamin may reduce the risk of developing cataract by around nine per cent.
Results of the February, 2014 trial in nearly 15,000 men, published in the Ophthalmology, suggested that long-term supplementation with a multivitamin may also reduce the risk of developing nuclear cataract by 13 per cent.
Nuclear cataract, which occurs at the centre of the lens, is the most common variety of cataract associated with the ageing process.
Equally, a research published back in 2005 in Archives of Ophthalmology suggested that vitamin supplementation, in particular vitamin E, for a period of five years lowered women’s chances of developing this visual condition.
So, what other food items helps to lower risk of cataract?
• Salmon. Salmon is rich in astaxanthin, a carotenoid that gives salmon and lobster their reddish colour. One study found that women who ate fish three times a week reduced their risk of cataracts by 11 per cent when compared to women who only ate fish once a month.
• Green tea. Researchers from the University of Scranton found that tea, both black and green, reduced glucose levels in the eye lens of rats and cut their risk of cataracts in half.
• Carrots. Carrots are good for the eyes. One of the powerful nutrients in carrots is lutein, which is a major component of many yellow and orange fruits and vegetables.
• Eggs. Egg yolks contain generous amounts of both leutein and zeanxanthin that protect against the sun’s harmful rays.
• Avocados. Avocados are dense in nutrients. They contain lutein, beta-carotene, vitamin C, vitamin B6, and vitamin E that are all helpful in preventing cataracts.
• Broccoli. Broccoli is loaded with both lutein and zeaxanthin, powerful nutrients that lower inflammation and prevent free radicals from damaging sight. Broccoli also contains sulforaphane, an antioxidant that protects eyes from the sun’s damaging rays.