Subjects will be randomly assigned to one of two treatment groups: either a placebo or the curcumin supplement (465 milligrams of Theracurmin™ of which 30 mg is curcumin). The investigators expect the people receiving the curcumin supplement to show less evidence of decline and fewer after 18 months than those receiving the placebo. The investigators believe cognitive decline and treatment response will vary according to a genetic risk for Alzheimer's.