Patsy Catsos, MS, RDN, LD

Patsy Catsos, MS, RDN, LD

Patsy Catsos, MS, RDN, LD


  • Registered, licensed dietitian with expertise in GI disorders
  • Nutrition consultant, FODMAP educator and writer, recipe developer
  • Member of the Academy of Nutrition and Dietetics and the Crohn's and Colitis Foundation of America


Patsy Catsos, MS, RDN, LD is a registered dietitian nutritionist with a private practice in Portland, Maine. She happily divides her time between caring for her own patients, developing recipes, blogging, keeping tabs on the latest digestive health research, and teaching other healthcare providers how to help their patients get great results.

Patsy has been using the FODMAP approach with irritable bowel syndrome (IBS) patients since 2008. After reading the early peer-reviewed literature about FODMAPs out of Australia’s Monash University Department of Gastroenterology, she set about developing a program to help her patients with IBS free themselves from the devastating symptoms of IBS. Keenly interested in digestive health and nutrition since her own diagnosis with ulcerative colitis 25 years earlier, she had never seen a dietary approach for managing gastrointestinal symptoms produce such fast, effective results. Her 2009 book, IBS—Free at Last! introduced consumers and health care providers to the power of the FODMAP elimination diet. The latest edition of her book and program, now titled The IBS Elimination Diet and Cookbook, was published in 2017 by Harmony Books, an imprint of Penguin Random House. She is also the author of The IBS-Free FODMAP Toolkit for RDNs, a collection of reproducible patient handouts, forms, and nutrition care planning advice for healthcare professionals.

Patsy is a professional member of the Crohn’s and Colitis Foundation of America and the Academy of Nutrition and Dietetics. She is an active member and a past-president of the Maine Academy of Nutrition and Dietetics; she was honored as Maine's 2014 Outstanding Maine Dietitian of the Year.


Ms. Catsos earned a bachelor’s degree in Nutritional Science at Cornell University and a master’s degree in Nutrition at Boston University. She completed her internship at Boston’s Beth Israel Hospital.

Ms. Catsos devotes significant time and energy to her own continuing education; she attends multidisciplinary symposiums nationally and internationally to bring her workshop attendees, patients, and readers cutting-edge information directly from researchers working in nutrition and functional gut disorders.

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