Faculty and Staff

Diane Stadler GPHN Program Director

Diane Stadler, PhD, RD, LD 

GPHN Program Director, Dietetic Internship Director, Associate Professor

Dr. Stadler received a BS in Special Studies with an emphasis in Genetics and Development from Davidson College, an MS in Nutrition Science from Virginia Tech, and a PhD in Human Nutrition from the University of Iowa. She completed a post-graduate fellowship at the Kennedy-Krieger Institute/Johns Hopkins Hospital and focused in nutritional interventions for children with developmental disabilities and/or gene disorders. She worked with dietetic interns at the University of Iowa and directed the Nutrition Science and the Coordinated Masters Programs at the University of Utah before joining the faculty at OHSU in 2000.

Dr. Stadler is an Associate Professor of Medicine and Director of the Graduate Programs in Human Nutrition at OHSU.  Her clinical work and research has focused on dietary interventions for the treatment and prevention of disease including:

  • Nutritional rehabilitation of severely malnourished children in Zambia, Africa
  • Nutrition education and growth monitoring of infants and young children at risk for malnutrition in the rural mountainous region of eastern Honduras
  • Dietary treatment of children with rare genetic disorders
  • Use of extremely high fat ketogenic diets for children with severe, unresponsive seizure disorders
  • Comparing the health risks and benefits of very low-and high-complex carbohydrate diets for weight loss in obese adults
  • School-based interventions for diabetes prevention
Melanie Gillingham - Master's Program Director

Melanie Gillingham, PhD, RD

Master's Program Director, Associate Professor

Dr. Melanie Gillingham is an Associate Professor in the department of Molecular & Medical Genetics and the Graduate Programs in Human Nutrition at Oregon Health & Science University. She received her BS in Nutrition from Texas Christian University, Ft. Worth, TX & her MS in Nutritional Sciences from University of Oklahoma, Oklahoma City, OK & completed her PhD at University of Wisconsin-Madison, Madison, WI. Dr. Gillingham coordinates the Masters programs and maintains an active research laboratory. Her research interests are on the nutritional treatment of inborn errors of metabolism and the effect of diet on fatty acid oxidation. The mitochondrial fatty acid oxidation (FAO) pathway is critical for survival during periods of fasting and for the maintenance of normal body weight and insulin sensitivity. The Gillingham Laboratory has been investigating the metabolic consequences of genetic disorders in the FAO pathway including inherited deficiency of very-long chain acyl CoA dehydrogenase (VLCAD), long-chain 3-hydroxyacyl CoA dehydrogenase (LCHAD) and carnitine palmitoyltransferase type 1A (CPT1A) deficiencies. FAO disorders are inherited in an autosomal recessive manner and collectively have an incidence of 1:9000 live births. Infants with a FAO disorder typically present with hypoketotic hypoglycemia and Reye-like symptoms precipitated by fasting or illness. The treatment for long-chain fatty acid oxidation disorders has been primarily with a modified diet including avoiding long periods of fasting, and frequent high carbohydrate meals. We have been investigating alternative nutritional approaches including fish oil supplements, medium-chain triglyceride supplements prior to exercise, and high protein diet low-fat diets on the outcomes and complications of these disorders. Dr. Gillingham is an active member of the Genetic Metabolic Dietitians International, the Society of Inherited Metabolic Disease, American Society of Nutrition and The Academy of Nutrition and Dietetics.

Joanna Cummings Instructor

Joanna Cummings, MS, RD-AP, CNSC

Associate Dietetic Internship Director, Instructor 

Joanna received her Master of Science in Clinical Nutrition from Oregon Health & Science University (OHSU) and is a Registered Dietitian (RD) with advanced certification as a Certified Nutrition Support Clinician (CNSC).  Her clinical and research experience includes pediatric and adult nutrition, inherited metabolic disorders, oncology, and bone marrow transplant. Additionally, she has worked extensively on the development of nutrition education tools as the Leadership and Education in Neurodevelopmental Disabilities (LEND) trainee at the Child Development and Rehabilitation Center (CDRC) at OHSU, Research Dietitian at Children’s Hospital Colorado, Clinical Dietitian in Oncology at the University of Colorado and as an adjunct professor at the University of Northern Colorado.


Julie McGuire, MS, RDN, LD

Master's Program Coordinator, Instructor

Julie began her academic career at Whitman College in Walla Walla, WA, where she received a BA in Biology and Environmental Studies. After time spent volunteering with AmeriCorps and working in the field of clinical research, she returned to school and received a BS in Nutrition and Food Management from Oregon State University. She is an alumna from the program having completed her dietetic internship and MS in Clinical Nutrition at OHSU. Julie has worked as a clinical dietitian at Legacy Emanuel Medical Center and the VA Portland Health Care System. She has also instructed the Medical Nutrition Therapy course for the School of Biological and Population Health Sciences at Oregon State University. Julie's professional interests include nutrition-focused physical exam, oncology, and the application of clinical research to the field of nutrition. Professional affiliations include the Academy of Nutrition and Dietetics and the Oregon Academy of Nutrition and Dietetics. She is also a Nutrition Physical Exam Trainer for the Academy of Nutrition and Dietetics. Julie was awarded the Emerging Dietetic Leader award from the Oregon Academy of Nutrition and Dietetics in 2019. 

Sandra Van Calcar Assistant Professor

Sandra van Calcar, PhD, RD, LD

Associate Professor

Dr. van Calcar completed her undergraduate work at Oregon State University and Master's Degree in Nutritional Sciences from the University of Wisconsin-Madison. She then served as a metabolic dietitian in the Biochemical Genetics Program at UW-Madison and her practice included both patient care and clinical research for those with inborn errors of metabolism. She finished her doctorate degree in Nutritional Sciences from UW-Madison in 2009. Her dissertation focused on the use of glycomacropeptide (GMP) as a new protein source for treatment of phenylketonuria (PKU). Dr. Van Calcar joined the faculty of the Department of Molecular and Medical Genetics and Graduate Programs in Human Nutrition in 2014. Her current research interests focus on nutrition management of inborn errors of metabolism (IEM), with emphasis on classical galactosemia, fatty acid oxidation disorders and pregnancy in IEM. She is a founding member of Genetic Metabolic Dietitians International and currently Past-President of this organization. Membership in other national professional organizations include the Academy of Nutrition and Dietetics and the Society of Inherited Metabolic Disease.

FSS Co Director

Patricia Allen, PhD

Food Systems and Society Co-director, Associate Professor 

Dr. Allen is the founder and co-director of the M.S. program in Food Systems and Society. Her interest in and commitment to food-systems equity result from her experiences in farm and food labor work. She earned a B.S. in Political Economy at the University of California (UC) Berkeley;an M.S. in International Agricultural Development;and a Ph.D. in Sociology from UC Santa Cruz. Dr. Allen's work has focused on the social construction of society and environment; gender, race, and class in the food system; discourse and initiatives in social movements, and alternative imaginaries of food cultures. Her edited volume, Food for the Future: Conditions and Contradictions of Sustainability is one of the first texts to call attention to social justice in sustainable food systems. Her book, Together at the Table: Sustainability and Sustenance in the American Agrifood System, addresses social problems and social change in food systems. Prior to joining OHSU, Dr. Allen established the M.S. program in Food Systems at Marylhurst University. Before that she directed the Center for Agroecology and Sustainable Food Systems research and education program at the University of California where she conducted research on gender, alternative food initiatives, and food movements. At OHSU Dr. Allen teaches courses that include foundations in food systems and society, economic justice, applications of scholarly work in food systems change, and 

FSS Co Director

Sean Gillon, PhD

Food Systems and Society Co-director, Associate Professor 

Dr. Sean Gillon is an Associate Professor of Food Systems & Society in the Graduate Programs in Human Nutrition at Oregon Health & Science University (OHSU). He serves as Co-Director of the M.S. Program in Food Systems & Society. Dr. Gillon earned a Ph.D. in Environmental Studies from the University of California, Santa Cruz; and a B.A. in Global Studies from the University of Iowa. Dr. Gillon completed a Postdoctoral Research Fellowship on the University of Wisconsin – Madison’s National Science Foundation-funded Water Sustainability and Climate Project. Dr. Gillon’s interdisciplinary research engagements have focused on science, policy, and politics in the US food system and aim to improve outcomes through critical inquiry, policy, and practice. His work includes analyses of organic food regulation, the social and ecological dimensions of biofuel production, conservation and climate change in agriculture, agroecological science and practice, and equity and political economy in the food system. Dr. Gillon teaches courses including Food Policy and Politics, Food System Theory, Food Systems Inquiry, and the Capstone series in the MS in Food Systems and Society Program. Prior to joining the faculty at OHSU, Dr. Gillon served as Department Chair of Interdisciplinary and Applied Liberal Arts at Marylhurst University where he applied his interdisciplinary research and teaching interests to build innovative degree programs. Outside of academia, Dr. Gillon has managed small farming operations, conducted research for community food groups working for social justice, served non-profit organizations, and worked as a produce buyer.


Carol DeFrancesco, MA, RD, LD

Instructor, Senior Research Assistant

Carol DeFrancesco, MA, RD, LD is a Senior Research Associate of Medicine in the division of Health Promotion and Sports Medicine at Oregon Health & Science University (OHSU). She received her Bachelor of Science in nutrition from Oregon State University and her Master of Arts in Liberal Studies from Reed College. She graduated with honors from both institutions and was a member of the Oregon State University women's basketball team. Ms. DeFrancesco completed her dietetic internship at Brigham & Women's Hospital and Harvard Medical School in 1989. She joined the Division of Endocrinology, Diabetes and Clinical Nutrition at OHSU, working with Dr. William E. Connor and Sonja L. Connor conducting omega-3 fatty acid research, counseling in the Lipid Disorders Clinic and editing the Lipid News. In 1999, Carol joined the Division of Health Promotion and Sports Medicine to direct ATHENA (Athletes Targeting Healthy Exercise and Nutrition Alternatives) an award winning, eating disorder and drug prevention program for female athletes. She coordinates PHLAME (Promoting Healthy Lifestyles Assessing More Effects), a research project studying health behavior change in fire fighters. Carol trained as a Motivational Interviewing trainer in 2000 under William Miller PhD and has since been an active member of the international network of Motivational Interviewing trainers. She teaches sports nutrition, yoga and motivational interviewing at OHSU. She has published more than 20 peer-reviewed articles and is an accomplished speaker and motivational interviewing trainer.

Supporting faculty

Bert Connell, PhD, RD, LD

Jessie Pavlinac, MS, RD, CSR, LD

Sarah Larimer, MS, RDN, LD