Huberman LabDr. Tony Wyss-Coray on Huberman Lab: How blood resets aging
Parabiosis cut inflammation in aged mice via young blood factors; blood protein panels now assign organ age gaps that predict disease risk years before.
CHAPTERS
Young blood and parabiosis: reactivating the aged brain
Wyss-Coray describes how heterochronic parabiosis (joining circulation of young and old mice) revealed that circulating factors from young organisms can rejuvenate old tissues, including the brain. In old mice exposed to young blood, neural stem cells reactivate, inflammation decreases, neural activity improves, and memory performance increases.
- •Parabiosis model enables shared circulation between young and old mice
- •Young circulation improves old brain inflammation, neuronal activity, and memory
- •Neural stem cells in aged brains can be reactivated
- •Early findings emerged from muscle stem-cell aging work (Rando) and expanded to brain aging
Blood as more than a readout: biomarkers that may drive aging and disease
The conversation shifts from blood as a diagnostic window to blood as a causal influencer of organ function. Large-scale proteomics shows dramatic age-related shifts in thousands of circulating proteins, raising the question of which factors are drivers versus consequences of aging and neurodegeneration.
- •Thousands of blood proteins change systematically with age
- •Age signatures are often stronger than disease signatures (e.g., Alzheimer’s)
- •Key question: are protein changes causal or reactive?
- •‘Clocks’ can estimate age from blood protein patterns
Human translation: plasma fractions, Alzheimer’s trials, and plasma exchange
Wyss-Coray explains attempts to translate mouse findings into human studies, including injecting human plasma into mice and testing clinical-grade plasma fractions. He reviews early trials in Alzheimer’s/Parkinson’s and highlights therapeutic plasma exchange (TPE) studies suggesting possible cognitive/functional benefits.
- •Human young plasma can mimic young-mouse effects in mouse models
- •Plasma fractionation (via Grifols) helps identify active components
- •Small clinical trials in Alzheimer’s/Parkinson’s tested candidate fractions
- •Therapeutic plasma exchange + albumin showed benefits in a large (≈500) Alzheimer’s trial
- •Early data suggests promise but larger definitive trials are needed
What’s in “young blood”: removing harmful inflammation vs adding pro-youth factors
They unpack whether benefits come from diluting/removing age-related “bad” factors, adding “good” youth factors, or both. Wyss-Coray describes inflammatory proteins that rise with age and can be neutralized in mice, alongside growth and stem-cell-supporting factors that promote repair.
- •Aging blood accumulates inflammatory proteins that can impair cognition
- •Neutralizing some inflammatory factors improves function in old mice
- •Youthful blood also contains active pro-growth/pro-repair signals
- •Different cells respond differently due to distinct receptors
- •Challenge: identifying minimal effective “cocktail” of factors
Blood banking, Dracula lore, and historical blood practices
Huberman asks whether individuals should bank their blood and whether cultural myths like Dracula reflect intuitive knowledge about blood and vitality. Wyss-Coray argues pooled young plasma works in studies, reducing the need for personal banking, and notes there’s no evidence that drinking blood would reproduce transfusion-like effects.
- •Research often uses pooled donor plasma; individual banking likely unnecessary for this concept
- •Dracula/blood lore may reflect blood’s perceived link to life and vitality
- •No evidence on benefits of ingesting blood (absorption/degradation issues)
- •Historical practices like leeching may have had effects but are not equivalent to modern interventions
Organs age at different rates: protein-based organ clocks and disease risk
Wyss-Coray describes how organs and even cell types can age asynchronously. Using proteins in blood that originate from specific organs, his group builds ‘organ age’ estimates and shows that an ‘age gap’ (organ older than chronological age) predicts future disease risk in that organ.
- •Different organs follow distinct aging trajectories
- •Blood contains organ-derived proteins that can be used to estimate organ age
- •‘Age gap’ predicts future risk (e.g., older-appearing heart → higher heart disease risk)
- •Most people track close to chronological age; a subset deviates meaningfully
- •Company efforts aim to operationalize organ aging measures for prevention
Personalized prevention platform: tailoring interventions and monitoring response
The discussion covers how organ-age readouts could guide individualized interventions—medications, exercise, diet, or other lifestyle changes—then retest to see whether the targeted organ ‘gets younger.’ This approach also speaks to why many drugs fail: heterogeneity in disease subtypes and late intervention timing.
- •Use organ aging to choose targeted therapies rather than generic advice
- •Iterative testing can determine whether interventions work for a specific person
- •Potential to stratify complex diseases (e.g., Alzheimer’s) into subtypes
- •Drug trials may fail due to treating ‘all comers’ too late or without stratification
- •Repurposing existing drugs could succeed with better matching to risk profiles
NAD, NMN/NR supplements, and what the evidence does (and doesn’t) show
Huberman asks directly about NAD-boosting strategies and longevity claims. Wyss-Coray notes there’s no validated human intervention proven to extend lifespan, highlights that supplements may raise blood levels without proving clinical outcomes, and cautions about product instability and label inaccuracies.
- •No human intervention has been proven in trials to extend lifespan
- •NMN/NR can increase blood levels, but outcomes like frailty/lifespan aren’t established
- •Supplement quality is variable; many products don’t match labels
- •NMN may be unstable; sourcing and third-party testing matter
- •Exercise and dietary patterns have the strongest evidence base for health outcomes
Vitality vs longevity and ‘waves’ of accelerated aging across adulthood
They explore antagonistic pleiotropy—traits beneficial early in life may be harmful later. Wyss-Coray discusses ‘waves of aging’ in blood proteins, with a major inflection around ~35–40, and considers evolutionary explanations for why maintenance programs may weaken after reproductive years.
- •Antagonistic pleiotropy: youth-beneficial signals can shorten lifespan later
- •Large proteomic shifts occur around ~35–40 (in men and women)
- •Modern longevity gains largely come from hygiene, antibiotics, and chronic-disease treatment
- •Hormone pathways (GH/IGF-1) may boost vitality yet trade off with longevity
- •Field focus is increasingly on healthspan (function) vs lifespan (years)
Exercise as a blood-borne brain therapy: liver signals, clustrin, and intensity questions
Wyss-Coray describes experiments showing that blood from exercised animals transfers some brain benefits to sedentary recipients, and that exercised young blood may outperform young blood alone. He highlights liver-derived factors such as clustrin and other candidates, while noting mechanisms remain complex and multifactorial.
- •Exercise-induced blood factors can transmit cognitive/brain benefits in mice
- •Exercised young plasma may be more potent than non-exercised young plasma
- •Liver appears to release key factors that act on brain
- •Clustrin (apolipoprotein J) can partially mimic effects when administered
- •Different exercise modes may create different molecular signatures worth mapping
Injury, inflammation, and the risks of unproven regenerative injections
They discuss why healing declines with age, emphasizing immune aging, chronic inflammation, and extracellular matrix changes that impair repair. Huberman and Wyss-Coray caution against unregulated stem-cell injections, highlighting infection and severe adverse outcomes, and contrast these with more established approaches.
- •Age-related immune shifts favor nonspecific inflammation over precise repair
- •Extracellular matrix remodeling (e.g., collagen changes) can hinder healing
- •Unregulated stem-cell injections can cause severe infections and neurologic harm
- •Translation requires controlled dosing, safety testing, and blinded trials
- •Emphasis: avoid experimental injections outside rigorous clinical oversight
PRP and exosomes: what they are and what’s plausible
Wyss-Coray explains platelet-rich plasma (PRP) as an autologous concentrate of platelet growth factors used for wound healing and some injuries. He describes exosomes as vesicles carrying proteins/RNA/lipids that may mediate intercellular signaling and could be useful diagnostically or therapeutically, though clinical evidence varies.
- •PRP: platelet granules deliver concentrated growth factors for repair
- •Typically derived from one’s own blood; used in some sports and fertility contexts
- •Exosomes: vesicles carrying proteins, RNAs, lipids, metabolites
- •Potential for diagnostics (signals from tumors/organs) and therapies
- •Field is young; mechanisms and validated indications are still developing
Environment, diet quality, and fasting: cautious interpretation of longevity claims
They review cumulative exposure concerns (plastics, pesticides, EMFs) and the practical difficulty of isolating long-term effects. On fasting, Wyss-Coray emphasizes inconsistent definitions and mixed animal data, with limited compelling human trial evidence, while agreeing that constant snacking is likely maladaptive.
- •Long-term cumulative exposure to modern chemicals is hard to quantify causally
- •Fresh, minimally processed foods are a practical risk-reduction strategy
- •Organic vs non-organic differences can be smaller than assumed depending on context
- •Fasting/intermittent fasting lacks standardized definition and strong human outcome trials
- •Caloric restriction benefits in animals may not translate cleanly to humans; avoid constant eating
Sleep, CSF rejuvenation, and synaptic protein predictors of cognitive resilience
Wyss-Coray discusses how cerebrospinal fluid (CSF) composition changes with age and can influence brain function. He describes experiments infusing young CSF into old mice to improve cognition and myelination-related cells, and human CSF proteomics identifying synaptic protein signatures that strongly predict cognitive resilience independent of classic pathology markers.
- •CSF composition shifts markedly with age
- •Young CSF infusion into old mice improves cognition; oligodendrocytes/myelination are key targets
- •Human CSF proteomics links synaptic proteins to cognitive function
- •A ratio of top synaptic markers predicts resilience/decline across large cohorts
- •Signals change from early adulthood, suggesting gradual synaptic vulnerability over time
Lifestyle, social connection, light exposure, and future directions: cell-type aging clocks & genetic disease proteome maps
They connect established dementia risk modifiers (smoking, alcohol excess, education, obesity, poverty) with the need for mechanistic, personalized tools. Wyss-Coray previews new work estimating aging of specific cell types from blood proteins and describes a major project to map plasma proteome changes across monogenic diseases to infer pathways and disease relationships.
- •Many dementia risks are modifiable via lifestyle, though feasibility varies by context
- •Social connection may mediate benefits often attributed to moderate wine consumption
- •Light exposure and circadian alignment are discussed as major brain-health levers
- •New cell-type clocks: e.g., ‘older’ astrocytes predict Alzheimer’s risk; ‘older’ muscle cells predict ALS risk
- •Future goal: build a public atlas of plasma proteome signatures across thousands of monogenic diseases
