Gut Microbiome Plasticity | Peter Turnbaugh | 214

Short Summary: How diet shapes the gut microbiome and impacts health, with microbiologist Dr. Peter Turnbaugh breaking down the complex science.

About the guest: Peter Turnbaugh, PhD is a professor of microbiology and immunology at the University of California, San Francisco, where he leads a lab studying the gut microbiome’s role in nutrition and drug response.

Note: Podcast episodes are fully available to paid subscribers on the M&M Substack and everyone on YouTube. Partial versions are available elsewhere. Full transcript and other information on Substack.

Episode Summary: Nick Jikomes talks to Peter Turnbaugh about the gut microbiome’s response to dietary changes, focusing on high-fat diets, ketogenic diets, and their effects on health. They discuss the pitfalls of oversimplified diet labels in research, Turnbaugh’s studies comparing plant-based and animal-based diets in humans, and how these shifts rapidly alter gut microbes and short-chain fatty acid profiles. The conversation also covers the microbiome’s role in drug metabolism, its links to inflammation and autoimmunity (like multiple sclerosis), and the potential of ketogenic diets to modulate these processes via ketone bodies like BHB.

Key Takeaways:

The term “high-fat diet” in research is often misleading, as it can include high carbs and vary widely, complicating study comparisons.

In a 2014 study, switching humans to a plant-based (high-fiber) or animal-based (ketogenic, no-fiber) diet changed their gut microbiome within one day, showing its remarkable adaptability.

Ketogenic diets reduce Bifidobacterium in the gut, which may lower inflammation-linked immune cells (Th17), potentially aiding conditions like multiple sclerosis.

Short-chain fatty acids (e.g., butyrate) don’t just come from fiber; they persist even on zero-fiber ketogenic diets, hinting at alternative microbial pathways.

Gut microbes can activate or deactivate drugs, like antibiotics or digoxin, suggesting microbiomes may explain why drugs work differently across individuals.

Ketone bodies like BHB alone can mimic some ketogenic diet effects on the microbiome and immunity, simplifying research and hinting at therapeutic potential.

*Not medical advice.

00:00:00 Intro
00:05:34 High-Fat Diet Issues
00:11:00 Macronutrient Mapping
00:17:29 Metabolic Adaptability
00:25:59 2014 Study Design
00:34:01 Microbiome Flexibility
00:41:03 Fatty Acid Profiles
00:48:41 Bile and Gut Changes
00:55:09 Inflammation Links
01:00:11 Keto Diet Exploration
01:07:08 BHB Impact
01:14:21 Microbiome Products
01:19:35 Drug Response Research