no overall additional benefit from adding omega-3 fatty acids or lutein and zeaxanthin to the formulation. However, the study did find benefits in two subgroups of participants: those not given beta-carotene, and those who had very little lutein and zeaxanthin in their diets. Removing beta-carotene did not curb the formulation's protective effect against developing advanced AMD, which is important given that high doses of beta-carotene have been linked to higher risk of lung cancers in smokers. According to Dr. Emily Chew, "Because carotenoids can compete with each other for absorption in the body, beta-carotene may have masked the effect of the lutein and zeaxanthin in the overall analysis." References External links NEI's website about the AREDS study NEI's website about the AREDS2 study National Institutes of Health Ophthalmology Clinical trials