Dr. Alessio Fasano, who is considered the world’s leading expert in celiac disease and gluten-related disorders, returns for his second appearance on STEM-Talk. Although just 2 million Americans have celiac disease, an estimated 20 million Americans suffer from gluten sensitivity. Alessio is a professor and director of the Mucosal Immunology and Biology Research Center at Massachusetts General Hospital. In addition to celiac disease and gluten-related disorders, Alessio’s research is also focused on the microbiome, intestinal permeability and autoimmune disorders, which he discussed in his first interview on STEM-Talk, episode 20. Since Alessio’s first appearance on STEM-Talk in 2016, he has published two books, “Gluten Freedom” and “Gut Feelings: The Microbiome and Our Health,” which we discuss in today’s interview. We also talk to Alessio about an exciting new project that’s bringing together an international consortium of researchers and scientists for a long-term study that will follow infants who are genetically at risk of developing celiac. Alessio is a researcher and physician who wears many hats. He is the director of the Center for Celiac Research and Treatment and chief of the Division of Pediatric Gastroenterology and Nutrition at Mass General Hospital. He also is a professor of pediatrics at Harvard Medical School and a professor of nutrition at Harvard’s T.H. Chan School of Public Health. Show notes: [00:03:58] Marcas opens the interview welcoming Alessio back to STEM-Talk, mentioning that since his last appearance he has written two books: Gluten Freedom and Gut Feelings: The Microbiome and Our Health. Marcas asks Alessio how he became interested in pediatrics and gastroenterology. [00:05:42] Ken mentions that Alessio moved to the U.S. in the 1990s and spent 20 years in Maryland at the Center for Vaccine Development in Baltimore. Ken goes on to mention that while Alessio was there, he founded The Center for Celiac Research in 1996, and in 2003, Alessio accepted an offer to join Massachusetts General Hospital. Ken asks how that move came about. [00:08:53] Marcas asks about Alessio’s early career working on cholera, where he discovered the zonula occuldens toxin, the bacteria that causes cholera. Marcas asks Alessio to talk about this finding and the insights he gleaned from it. [00:16:03] Ken asks about Alessio’s discovery of zonulin, which is the molecule that modulates gut permeability in humans. Ken asks Alessio to share how this discovery led him to investigate celiac disease, which is triggered by gluten. [00:20:25] Ken asks Alessio what his thoughts are on why the medical community, historically, has not taken celiac disease seriously. [00:24:08] Marcas mentions that as we age, there is evidence that the gut becomes leakier, which is highly related to chronic inflammation. Marcas asks Alessio whether this happens to the gut over time due to diet and lifestyle rather than the typical aging process. [00:28:45] Ken mentions that there has been an increase in the diagnosis of celiac disease. Ken asks Alessio if that is due to an actual increase in the prevalence of the disease, or is it tied to a growing appreciation that clinicians have now for the disease? [00:29:32] Marcas mentions that Alessio’s book, Gluten Freedom, which he co-authored with his colleague Susie Flaherty, was referred to by the Celiac Disease Foundation as “a must have,” and “an excellent reference for those with gluten related disorders.” Marcas asks Alessio about this reception to his book. [00:31:24] Marcas mentions that the only viable treatment for individuals with celiac disease has been a gluten-free diet, with pharmaceutical companies having had little interest until recently in investigating the disease. Now there are more than 20 drug therapies in development for celiac. Marcas asks Alessio about the progress being made to develop pharmacological interventions for celiac.