The question: Does eating carrots really improve eyesight? Or are there other foods that may prevent a decline in vision that results from macular degeneration?
The answer: If you don't already have macular degeneration, eating more carrots could help prevent the age-related eye disease, thanks to their exceptional beta-carotene content.
Macular degeneration attacks the part of the retina called the macula, which is responsible for fine, detailed vision. The condition leads to a progressive loss of sight in the centre of the visual field. That means it becomes difficult to read a book, drive a car and recognize faces. The exact cause is unknown but risk factors include cigarette smoking, obesity and excessive sunlight exposure.
A diet low in fruits and vegetables is also linked with a greater risk of macular degeneration. Antioxidants in fruits and vegetables are thought to protect the retina from the harmful effects of free radicals, unstable molecules formed from cigarette smoke, pollution and ultraviolet light.
Research has found that people who consume higher amounts of three antioxidants in their diet – beta-carotene, vitamin C and vitamin E – have a significantly lower risk of developing the eye disease.
So, yes, carrots could help ward off macular degeneration. Besides carrots, other good sources of beta-carotene include sweet potato, winter squash, peaches, cantaloupe, kale and spinach.
To increase your intake of vitamin E, add nuts, seeds, wheat germ, avocado, whole grains and kale to your diet. Good sources of vitamin C include citrus fruit, kiwis, green peppers, broccoli and tomato juice.
Foods rich in a phytochemical called lutein are also are associated with a lower risk of macular degeneration. The best sources of lutein include kale, Swiss chard, collard greens, green peas, broccoli, Romaine lettuce, Brussels sprouts, nectarines and oranges.
Eating oily fish regularly has been shown to prevent developing macular degeneration in the first place and also help prevent the disease progressing to a more advanced form. One of the omega-3 fats in fish called DHA is necessary for the normal functioning of the retina. The best sources of DHA include salmon, trout, sardines, anchovies and herring.
If you already have macular degeneration, discuss antioxidant supplementation with your eye care specialist. A landmark study (the Age-Related Eye Disease Study or AREDS) published in 2001 found that, among 3,640 older adults with varying stages of macular degeneration, those taking a high dose combination of antioxidants and zinc reduced the risk of the disease progressing to its advanced form by 25 per cent. The special formula used in study contained vitamin C (500 milligrams), vitamin E (400 international units), beta-carotene (15 milligrams), zinc (80 milligrams) and copper (two milligrams).
Send dietitian Leslie Beck your questions at firstname.lastname@example.org. She will answer select questions, which could appear in The Globe and Mail and/or on The Globe and Mail website. Your name will not be published if your question is chosen.
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