The Truth About Fiber And Your Gut Health with Matt Amicucci, PhD

In this episode of The Mind–Gut Conversation, Dr. Emeran Mayer speaks with Dr. Matt Amicucci, food scientist and co-founder of OneBio, about the rapidly evolving science of dietary fiber and its role in gut health, metabolism, and long-term disease prevention.

Drawing on years of research at UC Davis and the development of Glycopedia — a database cataloging the fiber composition of over four thousand plants and natural products — Dr. Amicucci explains why fiber should be understood not as a single nutrient, but as a diverse family of molecules, each interacting differently with the gut microbiome to produce distinct health outcomes.

The conversation explores how modern food processing has created a widespread fiber deficit, why the average American consumes less than half of what current recommendations call for, and how emerging research is beginning to link specific fiber types to specific microbial populations and measurable health benefits — from butyrate production and GLP-1 secretion to blood glucose control and reduced all-cause mortality risk.

This episode offers a grounded, science-based perspective on where fiber research is headed, and how personalized nutrition strategies built around the gut microbiome may reshape how we think about food and preventive health.

Key Topics Covered:

• Why dietary fiber is far more diverse and complex than most people understand
• How specific fibers feed specific gut microbes to produce targeted health outcomes
• The scale of the fiber deficit in the modern American diet
• The role of short-chain fatty acids and GLP-1 in metabolic health
• What personalized, microbiome-based fiber nutrition could look like

This is a practical, science-driven discussion for anyone interested in nutrition, the gut microbiome, and the future of food.