Conflict of Interests - none
Cochrane recently (2006) published a systematic review on the topic. This concluded: "The evidence as to the effectiveness of antioxidant vitamin and mineral supplementation in halting the progression of AMD comes mainly from one large trial in the USA. The generalisability of these findings to other populations with different nutritional status is not known. Further large, well-conducted randomised controlled trials in other populations are required. Long-term harm from supplementation cannot be ruled out. Beta-carotene has been found to increase the risk of lung cancer in smokers; vitamin E has been associated with an increased risk of heart failure in people with vascular disease or diabetes." (http://www.cochrane.org/reviews/en/ab000254.html) This is included as part of the answer by the NLH Q&A Service which includes a bit more detail (http://www.clinicalanswers.nhs.uk/index.cfm?question=5074)