Hi Reader,

Where is longevity headed? We've been hearing about 100+ biomarkers, peptides, and hormones—but is that what's really around the corner?

I just got back from three days at Eudemonia in Palm Beach, and I have thoughts. Today I'll share the topic I'm most excited about in longevity right now, plus the one I'd tell you not to spend money on yet.

Hang on - this is a big newsletter issue (and totally worth it!).

The topic I'm most excited about is also the one I'm quite dubious of

I went to three booths and a happy hour all on regenerative therapies—specifically CellCoLabs, SHA Longevity, and Stemregen.

Quick primer: regenerative medicine uses your body's own repair mechanisms to heal or rejuvenate tissue.

The main players are stem cells (cells that can become different cell types) and exosomes (tiny vesicles that cells release to communicate with each other—think of them as cellular text messages carrying instructions).

Here's what I found:

Most companies had compelling mechanism data ("this activates X pathway!") but thin outcome data ("...and in 47 patients over 3 months, inflammation markers dropped by..."). The industry is racing ahead of evidence. Which, honestly, isn't new in longevity 😅

My take? This is worth watching closely. Some of it will probably work. But we're not there yet on knowing which therapies, for which conditions, at what dose, with what safety profile over what timeline.

If someone's pitching you stem cell treatments, ask these questions:

• What are you actually measuring as outcomes? (Not just "I feel better")
• What's your follow-up period?
• Who are you specifically NOT treating? (If they say "everyone can benefit" that's a red flag)
• Where are you sourcing cells and how are you processing them?

Don't mortgage your house for this yet. But keep watching.

I went down a skin longevity rabbit hole (completely unplanned)

Confession: I tried every skin longevity product on the expo floor. Young Goose and OneSkin were the primary exhibitors.

But I didn't buy anything at the conference.

Instead, I went home and fell down a rabbit hole for several hours because the science is very interesting but outcomes less validated than for more "traditional" ingredients.

Here's the thing: even if your skin has very little to do with whether you'll live longer, it is your most visible aging biomarker. It's also one of your most accessible tissues for intervention.

And unlike systemic therapies where you're navigating pharmacology and compliance, topical delivery is relatively straightforward.

What actually has strong evidence for skin aging (and how it works):

• Retinoids – Bind to skin cell receptors → increase cell turnover + stimulate collagen production while blocking the enzymes that break it down. Decades of data. New encapsulation tech reduces irritation without sacrificing efficacy.
• Vitamin C (L-ascorbic acid) – Required cofactor for collagen synthesis (your body literally can't make collagen without it). Also neutralizes free radicals. Caveat: oxidizes quickly, so formulation matters.
• Sunscreen – Unsexy but probably the most effective anti-aging intervention. UV radiation damages DNA and degrades collagen directly. Most "skin aging" is actually photoaging.
• Alpha hydroxy acids (glycolic, lactic) – Break bonds between dead skin cells to increase turnover. At higher concentrations, signal fibroblasts to produce more collagen.
• Niacinamide – Precursor to NAD+, which skin cells need for energy and repair. Strengthens barrier, reduces inflammation. Less irritating than retinoids.
• Peptides – Signal peptides (like Matrixyl) can tell fibroblasts to make more collagen. Challenge: many are too large to penetrate the skin barrier at therapeutic concentrations.

The problem? Most products are the supplement industry playbook (really, skincare products are supplements): throw 47 ingredients in a serum, hope something works, make vague claims about "rejuvenation."

If you can't show me that your molecule penetrates the stratum corneum at therapeutic concentrations, we're talking about expensive moisturizer. (In all fairness, OneSkin did show me data that their peptides do get absorbed.)

I bought fish and a fasting workaround

Two things made it from the expo floor to my credit card:

​Seatopia - Not supplements. Not peptides. Seafood.

They're the only seafood company lab testing every batch for microplastics (zero detectable), mercury (under 0.1 ppm, way below FDA limits), and omega-3 content. Fish raised on microalgae-based feeds instead of the corn/soy/canola disaster. Low-density, antibiotic-free. Sushi-grade.

Why this matters for longevity: the omega-3 data is probably more robust than half the experimental compounds we're all chasing. Higher omega-3 index correlates with reduced cardiovascular disease, better cognitive function, and lower all-cause mortality. But most people either aren't getting enough or they're getting it from contaminated sources.

The thing that still has me scratching my head: ships in plastic packaging, consistently tests at zero detectable microplastics. Something about their processing and blast-freezing, but I need to understand this better.

​Mimio - The fasting mimetic I didn't know I needed.

I've tried prolonged fasting. The benefits are real—autophagy activation, metabolic shift, fat loss. But the hunger (and hair loss)? Absolutely not worth it for me personally.

Mimio replicates the four key metabolites your body produces after 36 hours of fasting (spermidine, nicotinamide, PEA, OEA) without actually fasting. Seven years of UC Davis research went into this. Their clinical trial showed improved hunger control, better metabolic markers, reduced inflammation—while people were eating normally.

The lifespan extension in model organisms was 96%. Which, yes, is model organisms (not humans), but the mechanistic data is compelling. I'm trying it out for a few months and will report back.

Going to a longevity conference and coming home with fish feels very on-brand.

Wellness and longevity just merged

I used to separate these cleanly: wellness was non-clinical stuff (meditation, supplements, biohacking gadgets), longevity was medical interventions (GLP-1s, hormone therapy, prescription protocols).

After Eudemonia, I'm retiring that framework entirely.

New model: "Healthcare you actually want" versus everything else.

Healthcare you want = stuff you're excited to engage with. Makes you feel better, perform better, look better. Could require a prescription or not—turns out people don't care about that distinction. They care whether it works and whether engaging with it feels like self-optimization rather than disease management.

Everything else = healthcare you'd rather not think about. The colonoscopies and chronic disease management we do because we have to, not because we want to.

This might sound like semantics but it's a massive shift in how we should be building companies in this space.

The companies that understood this at Eudemonia? Their products felt like luxury goods, not medicine. Messaging was aspirational, not fear-based. They got that the future of longevity isn't scaring people into healthspan—it's making healthspan something people actually want to pursue.

This is where wellness and longevity converge. It's probably where the money is too.

⚡ Longevity Science Quick Hits!

🎵 Daily Music Cuts Dementia Risk by 39%

Monash analysis of 10,800+ seniors found regular music listening reduced dementia odds by 39%, instrument playing by 35%, combined activities by 33%. Memory and cognition improvements across the board. This is a zero-barrier intervention that likely works through neural plasticity. Put this in the same category as exercise for brain health, but easier 😆

🗣️ Speaking Multiple Languages Halves Accelerated Brain Aging Risk

Pan-European study of 80,000 adults (51-90): monolinguals twice as likely to show rapid aging biomarkers. Each additional language amplified protection through cognitive stimulation. Longitudinal data confirmed sustained benefits. Never too late to start learning (pulls out Duolingo).

🧬 Rare T Helper Cells Clear Senescent Cells in Supercentenarians​

Researchers identified T helper cells expressing Eomesodermin that ramp up with age to eliminate senescent cells. Abundant in people living past 110, depleting them in mice accelerated aging. This reframes immune aging as adaptive rather than just declining. Could enable new diagnostics and targeted senolytic approaches.

⚠️ High Tyrosine Levels Linked to Shorter Lifespan in Men

Mendelian randomization in 400K+ people: genetically elevated plasma tyrosine associated with 2-5 year reduction in male lifespan (not women), likely through inflammation and cardiovascular strain. This is early research proving there's more to the debate about protein being good or bad for longevity. Not to mention, there are more sex difference in longevity interventions showing up.

📊 Caloric Restriction Still Beats Everything

Nature meta-analysis across species: CR delivers most consistent lifespan extensions (30-50% in some organisms) through autophagy and inflammation reduction. Rapamycin closely mirrored effects. Metformin? Mixed, often negligible. Hype train needs to meet data. CR-inspired approaches plus rapamycin = best evidence-based bet at the moment.

Where You Can Find Me

👂 Molecular You Webinar – Dec 3, Virtual. This is geared toward clinicians but anyone can join! We'll be discussing precision longevity.

🚀 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!

👱🏻‍♀️👩🏻‍🦰👩🏻👧🏽👧🏾 Livelong Women’s Health Summit – April 17-18, 2026, SF, CA. Delighted to join 50 other thought leaders in speaking on

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What I'm thinking about this week

The signal-to-noise ratio in longevity has never been worse. More tools than ever (peptides, exosomes, AI aging clocks) but we're still figuring out what works at scale.

The people doing real work in this space aren't the ones making the biggest claims. They're the ones asking the hardest questions.

I want to hear from you: I learned way more at Eudemonia than I could fit in one newsletter—women's health protocols, peptide deep dives, what's actually happening with biological age testing, and more.

What do you want me to dig into next? And what are you most excited about—or skeptical of—in longevity medicine right now? Hit reply – I read every message!

Hillary Lin, MD

Co-Founder & CEO

​Care Core​

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