This episode features Prof. Dirk Haller from Technical University of Munich (Germany) speaking about his work in the field of nutritional immunology, trying to unravel how immunity and gut microbiota interact with metabolism, ultimately impacting the emergence of chronic diseases. He focuses on how microbe-host interactions in the gut impact inflammatory or tumorigenic responses – essentially, the microbiota adapts and this drives disease progression. He sees the gut microbiota as a new dimension in nutrition science, with nutrients shown to trigger metabolic changes and impact the microbial environment in the gut. Interestingly, circadian rhythms (which also impact metabolism) seem to establish within the first year of life; and when a relevant microbial community is removed from the host for a week or two, it still shows diurnal oscillations. Lots of uncertainty still exists within the field, however. Prof. Haller recommends that gut microbiome studies report the timing of fecal sample collection, as it can be a major confounder. The metabolic output of microorganisms doesn’t correlate directly with the metabolic health of the host, so much more research needs to be done. Episode abbreviations and links: Paper on circadian rhythms in infant fecal samples: Diurnal rhythmicity of infant fecal microbiota and metabolites: A randomized controlled interventional trial with infant formula Paper on nutrition-microbiota interactions in pediatric Crohn’s disease: Exclusive enteral nutrition initiates individual protective microbiome changes to induce remission in pediatric Crohn’s disease About Prof. Dirk Haller PhD: Prof. Dirk pioneered the field of nutrition and microbiome research, and over the past two decades, he developed highly innovative and truly interdisciplinary research at the borders of different scientific fields. He finished two study programs emphasizing human nutrition and microbiology, before becoming engaged with the fascinating world of commensal microbes in the digestive tract and their impact on human health and diseases. He holds the Chair of Nutrition and Immunology at the Technical University of Munich and chronic intestinal inflammation became his prime research paradigm. In more than 250 publications, he developed ground-breaking and novel concepts to the question of how the non-infectious community of commensal bacteria contributes to the pathogenesis of chronic pathologies in the digestive tract. He developed Priority and Collaborative Research Programs thereby building microbiome research in Germany. Receiving the Main Award of the German Society of Medical Microbiology in 2015, the distinguished Research Award of the United European Gastroenterology Association in 2021, and the recognition as Highly Cited Scientist in 2024 highlights his global scientific reputation across disciplines. Sign up for our monthly newsletter Follow us on LinkedIn, Bluesky, X, Facebook, Instagram, Threads