The invention relates in part to a method of maintaining heavy metal homeostasis in healthy humans, comprising chronically administering to healthy humans a pharmaceutical composition consisting of from about 1 mg to less than about 200 mg of Posiphen or a pharmaceutically acceptable salt thereof together with one or more pharmaceutically acceptable excipients, on a once a day basis. By virtue of this method, prophylactic treatment of a potential disease state such as a neurodegenerative disease, cardiovascular homeostasis, cancer, vital organ homeostasis, and the like. The invention also relates in part to a method of restoring heavy metal homeostasis in sick patients, comprising chronically administering to a sick patient a pharmaceutical composition consisting of from about 1 mg to less than about 200 mg of Posiphen or a pharmaceutically acceptable salt thereof together with one or more pharmaceutically acceptable excipients, on a once a day basis. By virtue of this method, treatment of a potential disease state such as a neurodegenerative disease, cardiovascular disease, cancer, vital organ dysfunction and heavy metal dis-homeostasis, and the like.