This is the conclusion of this paper from the Indian Journal of Ophthalmology:
The results are consistent with the hypothesis that increasing dietary intake of foods rich in carotenoids may reduce the risk of developing AMD. A significant trend was seen for a decreased risk for AMD among subjects with greater intake of carotenoids, especially lutein/zeaxanthin. This study also indicates that prevalence of AMD increased with increasing age and was common in patient having diabetes. Results also confirmed that higher prevalence of AMD in those who drink alcohol and smoke cigarette heavily. Alteration in these modifiable risk factors assumes greater importance if viewed within the context of greater health benefits not necessarily limited to AMD. Most importantly, identifying dietary strategies to prevent or retard the onset of AMD will have a major impact on the burden of blindness and visual impairment among the elderly.