In this episode, I return to a conversation I promised to continue - sitting back down with Prof Tim Spector, MD, to explore everything that has changed in microbiome science since Episode 224. Tim and the ZOE team have now published a landmark Nature paper with 34,000 microbiome samples, run a clinical trial comparing personalized nutrition against government guidelines, and Tim has published a book on fermentation science.

We cover why most probiotics are scientifically obsolete, a practical ranked guide to fermented foods, the TMAO pathway linking gut bacteria to cardiovascular risk, and the estrobolome - the gut bacteria that recycle estrogen in women. If you have the gut health basics in place, this conversation tells you what to prioritize next.

What We Cover

Building a healthier gut microbiome is less about one dramatic intervention and more about consistent, moderate changes compounding over time. This conversation gives you the clearest picture yet of which changes to prioritise.

To connect with the guest, follow Tim Spector on Instagram at @tim.spector and explore ZOE at zoe.com.

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Simon Hill, MSc, BSc (Hons)

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