The vision supplement I take is based on the AREDS2 formula, but it contains a lot of zinc -- 80 mg in the recommended daily serving. Is it necessary, and safe, to take this much zinc every day?
The Age-Related Eye Disease Studies (AREDS and AREDS 2) are two of the largest studies on supplements for eye health. The formulation used in the first AREDS study included 80 mg of zinc (as well as other ingredients) and was shown to slow the progression of age-related macular degeneration (AMD) when taken on a daily basis. However, this amount of zinc is double the upper tolerable level for adults (see the Cautions section of the Zinc Review for concerns with excessive intake of zinc) -- and may not be necessary. In fact, the second AREDS study, AREDS2, found that a formulation which contained a much lower dose of zinc was just as effective in helping to slow the progression of AMD as the formulation with the higher dose of zinc.