Mind & Matter
Whether food, drugs or ideas, what you consume influences who you become. Learn directly from the best scientists & thinkers alive today about how your mind-body reacts to what you feed it.
The weekly M&M podcast features conversations with the most interesting scientists, thinkers, and technology entrepreneurs alive today.
Not medical advice.
At M&M, we are interested in trying to figure out how things work, not affirming our existing beliefs. We prefer consulting primary rather than secondary sources and independent rather than institutional voices. If we encounter uncomfortable truths or the evidence suggests unfashionable ideas may be valid, so be it.
As the host, my aim is to help you better understand how the body & mind work by curating & synthesizing information in a way that yields science-based insights that you can choose to use or disregard in your own life. Taking ownership of your health starts with taking ownership of your information diet.
I am motivated to connect the dots and distill general principles from what I learn, preferring to ask questions and play devil’s advocate to debating or incessantly pushing my own viewpoint.
My beliefs:
- Taking ownership of your health starts with taking ownership of your information diet.
- All knowledge is provisional and we must work hard to prevent ourselves from becoming attached to our favorite ideas & preferred conclusions.
- Wisdom comes from an iterative, trial-and-error process of learning and unlearning. Letting go of pre-conceived notions can be painful, but pain is information.
Sometimes modern discoveries teach us we must unlearn received wisdom. Other times, modern information overload & historical chauvinism cause us to forget ancient wisdom which stills applies. The framework for learning that I embody is inspired by three Ancient Greek maxims inscribed in the Temple of Apollo at Delphi:
- “Γνῶθι σεαυτόν” (Know thyself)
- “Μηδὲν ἄγαν” (Nothing in excess)
- “Ἐγγύα πάρα δ Ἄτα” (Certainty brings insanity)
Mind & Matter
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 talks to Peter Turnbaugh 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.
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.
Related episode:
- M&M #203: Metagenomics, Microbiome Transmission, Gut Microbiome in Health & Disease | Nicola Segata
*Not medical advice.
All episodes, show notes, transcripts, etc. at the M&M Substack
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