Charles B. Stephensen

Charles B. Stephensen

Position Title
Research Leader, Western Human Nutrition Research Center Adjunct Professor, Department of Nutrition UC Davis



  1. Ph.D., Department of Immunology and Infectious Diseases
  2. Johns Hopkins University School of Hygiene and Public Health


Charles B. Stephensen, Ph.D., is Research Leader of the Immunity and Disease Prevention Research Unit at the U.S. Department of Agriculture’s Western Human Nutrition Research Center located at the University of California, Davis.  He is also an Adjunct Professor of Nutrition and member of the Program in International and Community Nutrition at U.C. Davis.  Dr. Stephensen's research examines how nutrition affects immune function and the risk of infectious or inflammatory disease, as well as how infectious diseases affect nutritional status.  Dr. Stephensen’s research currently involves collaborative clinic- and community-based studies carried out in the U.S., Bangladesh and Laos.  These studies involve the impact of micronutrient supplements (vitamin A, vitamin D and zinc) on immune function, including vaccine responses.  In addition, diet may affect the composition of the intestinal microbiota and thereby affect immune function.  One current study is thus examining the effect of vitamin A supplementation on intestinal microbiota in Bangladeshi infants and is also examining the association of the microbiota with the response to early childhood vaccines.  A second, observational study in the U.S. is examining the association of typical dietary patterns with intestinal microbiota and the level of activation of the systemic immune system, including markers of systemic inflammation associated with risk of chronic disease.    

Dr. Stephensen obtained a B.S. degree in Biochemistry at the University of California, Davis, M. S. degree in Human Nutrition at Cornell University and a Ph.D. in Immunology and Infectious Diseases at the Johns Hopkins University School of Hygiene and Public Health.  He trained as a postdoctoral fellow in Virology at the Uniformed Services University of the Health Sciences.  Dr. Stephensen was a faculty member in the Department of International Health, School of Public Health at the University of Alabama at Birmingham for 10 years and also served as interim Chairman of International Health and interim Director of the Sparkman Center for International Public Health Education. In 1998 he moved to the USDA Western Human Nutrition Research Center.