A randomized, double-blind, placebo-controlled clinical trial was conducted to determine the effects of a low-dose (< 2 times the Recommended Dietary Allowance) micronutrient supplement containing trace minerals (zinc and selenium) and/or vitamins/provitamins (vitamin C, alpha-tocopherol, and beta-carotene) on the incidence of respiratory and urogenital infections in institutionalized elderly. After 2 years, there was a significant decrease in the mean number of infections in elders given trace elements (p < 0.01) but not vitamins.