149: Bryan Johnson's Disease Has Nothing to Do With Diet

Bryan Johnson was diagnosed with autoimmune gastritis in 2026, and within a day the internet had already decided it was his vegan diet — I don't think it's that simple.

In this episode I break down what autoimmune gastritis actually is, why Bryan's own data (crashed ferritin, failed iron absorption, a second autoimmune condition since he was 21) points to something deeper than food alone, and why both sides of this argument — "it's the diet" and "diet has nothing to do with it" — are missing the real pattern.

I walk through the genetics-plus-environment framework behind autoimmune disease, compare Bryan's lifestyle against how humans have lived for most of our history — sun exposure, food sourcing, community, caloric rhythm — and lay out the specific changes I'd make instead, most of which don't cost you anything. If you've ever wondered whether optimizing your health can go too far, this one's for you.

Thank you to this episode's sponsor, Peluva!

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Learn More:

2: 8 Key Primal Shifts for Ancestral Living: https://www.primalshiftpodcast.com/8-key-primal-shifts-for-ancestral-living/

59: Paleo, Keto, Carnivore [Navigating Dietary Changes as a Family]: https://www.primalshiftpodcast.com/59-paleo-keto-carnivore-navigating-dietary-changes-as-a-family/

In this episode:

00:00 Intro