Can a Blood Test Predict Alzheimer's?

Can a Blood Test Predict Alzheimer's?

Author: Josh Turknett, MD April 14, 2026 Duration: 28:31

A recent study published in Nature Medicine claims a blood test can predict when you'll develop Alzheimer's disease, and it got a lot of attention. But how well does it actually work, and should you rush out and get tested?

In this episode, we break down the study behind the headlines to understand what it really shows, where the major limitations lie, and what it means for anyone thinking about getting this kind of test.

Topics and Questions Covered

  • What P-Tau 217 is and why it's become the leading blood-based biomarker in Alzheimer's research.

  • How researchers built a predictive "clock" from blood test data and what that process required.

  • The important distinction between having pathology in your brain and actually developing dementia.

  • Who should and should not be getting tested.

  • What a large Norwegian population study reveals about the overlap between pathology and normal cognitive function.

  • How biomarkers like this might eventually fit into a broader, more personalized approach to prevention.

  • and more!

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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 (a Brainjo Production)
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