Almost Forever Podcast

What We Know About Rapamycin with Matt Kaeberlein

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One of the world's most respected gerontologists, Dr. Matt Kaeberlein has published more than 250 research papers and spent nearly three decades studying what slows aging. He joins Almost Forever hosts Renee and Melanie to separate what's real in longevity from what's hype, and to explain why he's staked his reputation on telling people the truth. Along the way: the remarkable study tracking tens of thousands of dogs, the compound he believes is the field's most promising, and a candid guide to telling a real expert from a talking head.
In our Mailbag: whether a healthy 45-year-old should consider rapamycin, if metformin really slows aging in people who aren't diabetic, and — if you could keep just one longevity supplement — which?

Myth or Method: Detox foot pads and castor oil packs — do they really draw toxins out of your body, or is something else going on?

Chapters:
0:00 The signal-to-noise problem
2:40 Myth or Method: Do detox foot pads and castor oil packs actually pull toxins out?
9:40 Meet Matt Kaeberlein — one of the world's leading aging scientists
10:33 The longevity hill he'll die on: the field's signal-to-noise problem
13:48 How to spot longevity misinformation — and the shift back toward science
17:42 The origin of the Dog Aging Project — and the light-bulb moment
22:32 Why companion dogs are the perfect model — and what 55,000 dogs reveal
28:29 Dobby: the German Shepherd who inspired it all
31:42 What rapamycin is, and why he chose it
37:09 mTOR as a "volume knob" — and why ours is always turned up
39:04 Rapamycin vs. caloric restriction — and why 800 calories isn't the answer
42:38 Cycling, dosing, and what we still don't know about rapamycin in humans
45:40 Rapamycin, fasting, the FMD, and autophagy — overlapping but distinct
51:16 What we can safely say about rapamycin in people
52:47 "Everything has side effects" — even exercise
54:10 The real evidence: dementia risk, vaccines, and the immune question
1:00:16 mTOR, protein, and the high-protein trend
1:04:33 Does rapamycin work better for women? The sex-difference data
1:07:47 Muscle, exercise, and what the New Zealand trial actually showed
1:11:20 What's next: the big trials that will finally give us answers
1:13:22 Mailbag: Should a healthy 45-year-old consider rapamycin?
1:15:06 Mailbag: Does metformin actually slow aging in healthy people?
1:20:00 Mailbag: If you could keep only one longevity supplement, which survives?

Guest Bio: Dr. Matt Kaeberlein is one of the world's foremost researchers on the biology of aging, with more than 250 peer-reviewed publications. He is the co-founder of the Dog Aging Project — a landmark study following tens of thousands of companion dogs to understand aging in real time — and a longtime investigator of rapamycin and the mTOR pathway. He has become a leading voice for scientific rigor and honesty in a field crowded with hype.

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