Get eye vitamins from your diet
DEAR DOCTOR: Do “eye vitamins” have any benefit at all? I know a lot of seniors who believe in them, but I’m skeptical.
DEAR READER: Vitamin supplements have been touted for nearly every condition, with scant evidence of their efficacy when compared with a healthy diet.
Lutein and zeaxanthin generally top the list of “eye vitamins.” That’s because these dietary carotenoids — related to beta carotene and vitamin A — help form retinal macular pigment. This pigment absorbs damaging light rays and thus protects the macula, the part of the retina responsible for detailed vision. Additionally, these carotenoids are antioxidants, protecting the eye from cellular damage.
Diets high in lutein and zeaxanthin have been associated with a lower risk of the late changes of macular degeneration. And higher blood levels of lutein and zeaxanthin have been linked to a decreased cataract risk. Leafy green vegetables such as lettuce, spinach, kale and parsley are high in these carotenoids, as are eggs, so a diet containing these foods may
help protect your vision.
In people who already have macular degeneration, antioxidants such as vitamin C, vitamin E, lutein and zeaxanthin do seem to slow the progression of macular degeneration. In fact, these antioxidants — when taken with zinc — are linked to a 28 percent reduction in late macular degeneration. People who substituted beta carotene for lutein and zeaxanthin reported similar benefits. Note, however, that beta carotene has been associated with increased lung cancer rates in people who smoke.
As for multivitamins, one of the studies assessed the potential effects of the multivitamin Centrum Silver and found a 22 percent relative increased rate of macular degeneration compared with a placebo.
My recommendation is to get most of these so-called “eye vitamins” from your diet. If you have risk factors for heart disease, you may find benefit with B vitamins, or if you have macular degeneration, you may benefit from antioxidant vitamins.
Robert Ashley, M.D., is an internist and assistant professor of medicine at the University of California, Los Angeles.