On call: Vitamin A and macular degeneration
Vitamin A and macular degeneration
Q. Experts say the safe daily consumption for vitamin A is less than 3,000 IU. I am 60 years old and have been diagnosed with macular degeneration. The doctors told me to take the AREDS (Age-Related Eye Disease Study, done by the National Eye Institute of the NIH) formula of antioxidant vitamins, which contains 28,640 IU of vitamin A (beta carotene) along with vitamins C and E, plus zinc and copper, in a daily dose. In addition, I eat a lot of vegetables and not much meat.
Since this much vitamin A is way over the amount you recommend, what should I do? I am younger than most patients with macular degeneration and could be on this formula for a long time. I want to save my vision but not damage my bones.
A. Your question shows that nutrition can be complex and confusing. You are right about vitamin A; data suggest that high (and low) amounts are linked to an increased risk of osteoporosis and fractures. But beta carotene does not carry the same risk, even though it belongs to the same antioxidant family as vitamin A and even though some of it is converted to vitamin A in the body. In fact, beta carotene seems quite safe. The one exception is that it appears to increase the risk of lung cancer in smokers. In high doses, it can also produce a yellowish complexion.