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Eye-Opening Ocular Vitamins and Supplements
Millions of men and women who might otherwise be active and healthy are struggling everyday with vision problems. Research shows that certain vitamins, minerals, and antioxidants can play a key role in protecting vision and maintaining eye health. In some cases, changes in diet and a daily regimen of high potency nutrients can slow or even stop the progression of some eye diseases such as macular degeneration, diabetic retinopathy, glaucoma, and cataracts.
Antioxidants
Vitamin C, Vitamin E, beta-carotene (pro-Vitamin A) and carotenoids (lutein and zeaxanthin) are strong antioxidants (i.e., they protect the eye against free-radical damage). Because of this, it seems reasonable to assume that strengthening of the eye’s defenses by increasing the intake of these vitamins would be helpful in preventing chronic aging eye diseases.
AREDS Study
The Age-Related Eye Disease Study (AREDS) reported a beneficial effect of antioxidants plus zinc in patients who have moderate-to-advance macular degeneration (i.e. those who have extensive intermediate size drusen or at least one large drusen or geographic atrophy in one or both eyes, or visual acuity worse than 20/32 that can be attributed to macular degeneration). The study showed that treatment with antioxidants plus zinc reduced the progression risk of moderate macular degeneration to advanced macular degeneration by 25%.
Vitamin supplements do not provide as much benefit to patients with minimal macular degeneration. These nutritional supplements do not prevent the development of macular degeneration, nor do they restore vision already lost to macular degeneration. In the AREDS study, nutritional supplements did not seem to prevent cataracts or keep them from getting worse over time, although other studies have shown some beneficial effects. Doses used in the study were: Vitamin C 500mg; Vitamin E 400 IU; beta-carotene 15mg; zinc 80mg, as zinc oxide; (copper should be taken with zinc, because high-dose zinc is associated with copper deficiency).
Smokers and ex-smokers probably should not take beta-carotene, as studies have shown a link between beta-carotene use and lung cancer among smokers.
Nutritional Supplements and Cataracts
Compared with non-users, the risk for cataracts is 60% lower among persons who use multivitamins or any supplement containing Vitamin C or E for more than 10 years. Vitamin C reduces the risk of cortical cataracts in women aged 60 years or less, and carotenoids reduce the risk of posterior sub capsular cataract in women who have never smoked.
A recent research report also suggests that lutein and zeaxanthin (the only carotenoids found in the lens) may retard aging of the lens. Higher intakes of protein, Vitamin A, niacin, thiamin, and riboflavin (i.e. Vitamin B-complex) are associated with reduced prevalence of nuclear cataract.
Research by the Nutrition and Vision Project (NVP), a cooperative effort of Harvard and Tufts University scientists, revealed that just a little extra Vitamin C might be a good thing for women’s eyes. Any protective effect of Vitamin C probably occurs well above the recommended dietary allowance of 75 mg/day for women, about the amount in an orange (women who smoke need more Vitamin C-110 mg/day).
The NVP Harvard Study also found that women who consume higher than recommended doses of Vitamin C may lower their risk for more than one type of cataract. Therefore, boosting the Vitamin C intake from both food and supplements to around 500mg/day is probably a good idea.
Bilberry
Herbal supplements in the U.S. has become increasingly popular in recent years. Bilberry has a long history of use for various eye conditions. The active components, flavonoid anthocyanosides, are potent antioxidants with a particular affinity for the eye and vascular tissues.
Interest in bilberry was first aroused during World WarII when British Royal Air Force pilots reported improved night visual acuity on bombing raids after consuming bilberries. Subsequent claims have been made that the administration of bilberry extracts results in improved night visual acuity, quicker adjustment to darkness, and faster restoration of visual acuity after exposure to glare. IN a report of 50 patients with age related cataracts, a combination of bilberry and Vitamin E delayed the progression of cataracts. Bilberry is also used to treat glaucoma.
Ginkgo Biloba
Freely available, ginkgo biloba extract has several biological actions which combine to make it a potentially useful agent in the treatment of glaucoma: improvement of central and peripheral blood flow, reduction of vasospasm, reduction of serum viscosity, antioxidant activity, platelet activating factor inhibitory activity, inhibition of apoptosis, and inhibition of excitotoxicity.
Of some concern is the bleeding tendency when herbs like ginkgo are taken along with Aspirin or other blood thinners because bleeding may occur inside the eye in patients taking ginkgo.
Pycnogenol
Otherwise known as maritime pine bark extract, this antioxidant is believed to boost the immune system, lower blood glucose in Type II diabetes patients, and slow the progression of diabetic retinopathy.
Dry Eyes
Recent studies of more than 32,000 women at Harvard University found that women who consumed a lot of omega-3 or flaxseed oil had a lower risk of dry eye syndrome. Men should avoid using flaxseed oil as there has been evidence of increased risk of prostate cancer with this supplement. Also, refrigerating omega-3 capsules has been shown to maintain the efficacy of the benefits of these capsules.
Reprinted with permission from my good friend and colleague, Dr. Donald S. Teig, Director of the Institute for Sports Vision in Ridgefield, CT.
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