Gerber early childhood nutrition expert

Michelle M. Pietzak

Assistant Professor of Clinical Pediatrics

“‘Let food be thy medicine and medicine be thy food.’ This was said by Hippocrates more than two millennia ago and still rings true today. Many of today’s chronic diseases, including obesity, fatty liver disease, food allergies, and celiac disease can be attributed to today’s Western dietary practices. Infants born via C-section and not breastfed can experience abnormal intestinal flora, a potential environmental trigger for many diseases. Today’s healthcare practitioners often focus on treating existing conditions with drugs rather than prevention with a healthy diet and lifestyle. What I most enjoy about being a Pediatric Gastroenterologist is teaching my patients, their families, and referring physicians that many gastrointestinal conditions can be treated with dietary management. By doing so, we may return to foundations laid by Hippocrates and others after him to prevent chronic illnesses in ourselves and our children through nutrition.”

Michelle M. Pietzak, MD, is Assistant Professor of Clinical Pediatrics at the University of Southern California, Keck School of Medicine in Los Angeles, California. In her practice, she cares primarily for children with autoimmune inflammatory bowel diseases (such as celiac disease, Crohn’s disease, and ulcerative colitis), short-bowel syndrome, and for those who have special nutritional needs requiring either intravenous nutrition or special formulas.

Dr. Pietzak is a member of several national and international committees, including the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition. She is part of a Scientific Advisory Board that develops guidelines and educational initiatives for the Children's Digestive Health and Nutrition Foundation, and is a member of the American Celiac Task Force, which successfully lobbied Congress to pass the Food Allergen Labeling and Consumer Protection Act of 2003.

Dr. Pietzak has been a co-author on numerous book chapters, papers, and abstracts—both peer-reviewed and in the lay press—describing the prevalence of celiac disease in the United States. In 2001, she was profiled in Living Without magazine’s “Our Favorite Gastroenterologists.”

As a leading researcher, Dr. Pietzak is the recipient of numerous grants, including one from the NIH to study autoimmune intestinal diseases, as well as the interactions between E. coli bacteria and the gastrointestinal tract. She has been recognized several times for presenting Posters of Distinction at various scientific conferences.

Dr. Pietzak received a BS in biology at Manhattan College in the Bronx, New York, and an MD at the State University of New York, Buffalo. She completed both her residency and fellowship in pediatric gastroenterology and nutrition at Children’s Hospital Los Angeles. She is board certified in both pediatrics and gastroenterology and practices as a pediatric gastroenterologist at Children’s Hospital Los Angeles. 

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