Can This Vaccine Help Prevent Alzheimer's?

Can This Vaccine Help Prevent Alzheimer's?

Author: Josh Turknett, MD May 7, 2026 Duration: 28:46

Can a shingles vaccine cut your dementia risk by 20%?

A series of landmark studies — published in Nature, Cell, and JAMA — say yes.

In this episode, Tommy unpacks the research: how natural experiments in four countries produced one of the most compelling signals in dementia prevention, what might explain the effect beyond infection prevention, and what it means for your own vaccination decisions.

In this episode:
00:00 — Introduction
00:52 — The new data on shingles vaccination and Alzheimer's risk
01:48 — The Stanford group and their regression discontinuity methodology
03:15 — How birthday-based eligibility creates a natural experiment (Wales, Canada, Australia)
05:28 — Results: a ~20% reduction in dementia diagnoses across all countries
06:52 — The Cell paper follow-up: benefits at every disease stage (unimpaired → MCI → dementia)
07:55 — Shingrix vs. Zostavax: the US natural experiment and a potentially larger effect
09:08 — Why does it work? Preventing illness, avoiding bed rest and disuse, immunomodulation
11:29 — Neuroinflammation and possible immune system "tuning" effects
12:27 — The sex difference: greater benefit in women in most (but not all) studies
15:52 — Summary of the evidence and what it means for dementia prevention strategy
17:36 — Josh's take: number needed to treat analysis
19:15 — Heterogeneous pathways to dementia and why vaccination fits the toolkit
21:13 — Practical advice: when to get vaccinated, repeat dosing, and personal risk assessment
25:36 — Wrap-up and how to submit questions

Links & Resources:

  • Shingles vaccine and dementia studies: Nature (Wales, 2025), Cell (Wales follow-up), JAMA/Lancet (Canada, Australia, US)
  • Flu vaccine and dementia: Neurology (2026)
  • Tommy's book: The Stimulated Mind

To submit a question for us to answer on the podcast, go to brainjo.academy/question.

To subscribe to the free Better Brain Fitness newsletter, join us when we record live, and get our Guide and Checklist to essential blood tests and nutrients, go to: betterbrain.fitness.

To learn more about how you can boost brain fitness with neuroscience-based musical instruction, head to brainjo.academy

Intro and Outro music composed and produced by Julienne Ellen

 


What does it really mean to have a fit brain, and how do we actually achieve it? That’s the central question explored in Better Brain Fitness (a Brainjo Production), a conversation guided by neurologist Dr. Josh Turknett and neuroscientist Dr. Tommy Wood. Moving beyond generic advice, each episode digs into the practical, often surprising science of cognitive longevity. You’ll hear discussions that translate complex research into actionable strategies, covering everything from nutrition and sleep to movement and mental challenge. The aim isn’t just about preventing decline, but actively building a resilient, high-performing mind that supports your passions and daily life. This podcast operates on the principle that our brain’s health is malleable at any age, and that understanding the underlying mechanisms empowers us to make better choices. Tune in for a nuanced look at how lifestyle intersects with neurology, stripping away the hype to focus on what evidence suggests truly works. It’s a resource for anyone curious about taking a proactive, informed role in their own cognitive well-being, ensuring the brain remains a robust partner for all the years ahead.
Author: Language: English Episodes: 100

Better Brain Fitness with Drs. Josh Turknett and Tommy Wood
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