A study published in the American Journal of Clinical Nutrition (Oct;86(4):1167-73) indicates that adequate zinc levels may help to prevent pneumonia in elderly nursing home residents. For one year to 617 nursing home residents over the age of 65 were given vitamin and mineral supplementation amounting to ½ of the RDA. Blood zinc levels were measured at the beginning and at the end of the study. Those with normal zinc levels had a 50% lower risk of developing pneumonia, and the death rate from other causes was 39% lower when compared to those with low serum zinc levels.