💪 Stanford MD, Internal Medicine Board Certified Physician
💪 Longevity, Healthspan, Proactive Health
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The free shot that might prevent dementia (for some!)
Published 4 days ago • 4 min read
Hi Reader,
Are you at Longevity Global Summit or A4M next week? Let me know!
I've been tracking my food this month — something I do quarterly to recalibrate after things get a bit wild with travel and the holidays.
At Thanksgiving, Gemini AI nailed it. Protein, carbs, fat — broken down by each item on the plate, with reasonable estimates for portion sizes. No manual logging. No scanning barcodes.
And as you'll see in this issue, that same leap in innovation is happening in longevity science, from drug discovery to dementia prevention.
In this issue:
💉 The *free* shot that might prevent dementia (major new data just dropped)
🤖 An AI just discovered an anti-aging drug by analyzing 2 million samples
⚠️ Why tyrosine supplements might be shortening men's lives
Gemini is a real multimodal AI hero, helping me track my nutrition. It's not 100% accurate (always assume calories are underestimated), but it's pretty good for a snapshot analysis!
The Free Shot That Might Do What Billion-Dollar Drugs Can't
On Monday, a study dropped in Cell that basically shouted: get your shingles shot.
You've probably heard some version of "shingles vaccine might prevent dementia" before. The first big study came out in April from Nature — a natural experiment in Wales showing ~20% reduced dementia risk over 7 years.
Interesting, but observational. Could be confounding. I filed it under "watch this space."
What's new: Researchers followed people who already had early cognitive decline and found the shingles vaccine reduced dementia mortality by 29.5 percentage points over 9 years. Not prevention — therapeutic effect.
The female effect is massive. That 29.5% is an average. For women: 52.3 percentage points. For men: statistically zero. (Men shouldn't skip it — the mechanism should help — but the current data is driven by women.)
It extends life, not just the diagnosis. All-cause mortality dropped 22.7 percentage points. This isn't just changing death certificates — it's slowing decline.
It prevents the first domino too. In cognitively healthy people, the vaccine reduced new MCI diagnoses by ~3.1 percentage points. It works across the entire disease course.
Why might it work?
Viral reactivation: Varicella-zoster hides in neurons. Reactivation triggers neuroinflammation and vascular damage. The vaccine keeps it dormant.
Immune training: Live-attenuated vaccines may tune the immune system to reduce brain inflammation broadly.
The Mixed Dementia signal: Effects were strongest for Mixed Dementia (Alzheimer's + vascular), suggesting broad neuroimmune pathways — not just amyloid.
Leading theories suggest that when the virus reactivates in nerve roots, it triggers a cascade of neuroinflammation that reaches the brain—accelerating cognitive decline long before clinical dementia appears.
The caveats:
Most data is on Zostavax (live-attenuated). Shingrix shows a signal too, but less data.
Still observational — no RCT yet.
This study is Wales data, replicating earlier Australian findings.
What you should actually do:
If you're 50+ and haven't gotten a shingles vaccine, this is your sign. It's free with most insurance (Medicare Part D, ACA plans, most employer coverage) — or ~$400 out-of-pocket if you're uninsured (GSK has assistance programs). The downside is... preventing shingles, which is awful anyway.
Even if the dementia effect turns out to be smaller than these studies suggest, the risk-benefit math is absurdly favorable.
This is what I mean by "major in the majors." While people chase $10,000/year experimental protocols, a two-dose vaccine series might be moving the needle more than anything else in the longevity toolkit.
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🤖 AI Discovers Anti-Aging Drug by Analyzing 2 Million Samples
Harvard's Gladyshev Lab built an AI platform (ClockBase) that analyzed 2M+ biological samples across 40+ aging clocks. Its top hit? Ouabain — a cardiac glycoside nobody was looking at. In 20-month-old mice, it reduced frailty, neuroinflammation, and improved heart function. The kicker: 2/3 of "anti-aging" interventions the AI analyzed actually accelerated aging.
Take-away: Drug discovery is getting industrialized. The platform is public at clockbase.org.
⚠️ The Tyrosine Trap: Why "More Protein" Isn't Always Better for Men A massive new study in Aging combined observational data with genetic causal analysis (Mendelian Randomization) to look at amino acids and lifespan. The results were stark: higher circulating tyrosine levels were causally linked to a shorter lifespan (~0.91 years lost). The Nuance: The effect was statistically significant only in men. The study suggests tyrosine (not its precursor phenylalanine) is the driver, potentially via the mTORC1 pathway or insulin resistance.
Take-away: While it's tempting to say men should restrict protein here, the reality is a bit more complex. I would say the only "maybe" take-away is to perhaps hold back on *extra* tyrosine supplementation (sometimes doe for dopamine/focus) particularly in men.
🦴 Collagen Study Shows Specific Ratio Matters — But Read the Fine Print
An npj Aging study found a 3:1:1 glycine-proline-hydroxyproline ratio extended lifespan in worms, improved grip strength in mice, and reduced biological age by 1.4 years in a small human trial. Sounds great — except it was co-authored by Avea Life AG, the company selling the product tested.
Take-away: The science on collagen peptide architecture is real and interesting. But I'd wait for independent replication before buying anything based on this study.
What I'm Thinking About This Week
One AI eyeballed my turkey and nailed my macros. Another AI sifted through 2 million biological samples and surfaced a drug no human was looking for.
The tools aren't just getting faster. They're finding things we wouldn't think to ask about.
I don't know exactly where this goes. But the distance between "cutting-edge research" and "thing on my phone" is shrinking faster than I expected...
Happy Holidays! And if you're at Longevity Global Summit or A4M, let me know!
Where You Can Find Me
🚀 The Longevity Global Summit 2025 – Dec 9-10, Novato, CA. Clinical Panel. I’m so excited to speak at the Buck Institute with the movers and shakers of longevity! Code SUMMITSPEAKER15 for 15% off
🎉 A4M Longevity Fest – Dec 12-14, Las Vegas, NV. This is oriented toward practitioners in longevity, with more clinical talks and exhibits. Betting we'll learn a ton here!
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