Dr. Richie's research focuses on the elucidation of factors that regulate cancer risk in individuals and in populations. Using an interdisciplinary research approach, the aim is to identify the roles and mechanisms of key factors, alone and in combination, which impact cancer risk with the ultimate goal of utilizing this information in the design and development of targeted prevention strategies. The major areas of focus include aging, nutrition, tobacco and race/ethnicity as regulators or determinants of cancer risk. Particular emphasis is given to factors related to the generation of and protection against oxidative damage. In an ongoing molecular epidemiology study of tobacco-related cancers in black and white Americans, metabolic and genetic factors that may be responsible, in part, for observed racial differences in tobacco related cancer rates are being investigated. In other studies, we are examining the role of glutathione, the major endogenous antioxidant in nearly all cells and tissues, in protecting against oxidative damage during aging and its relationship with cancer development at numerous sites.