Participants: Healthy, overweight older adults 
Dosage: 6 mg/day of spermidine supplemented orally for 13 weeks

Oxford scientists find that spermidine, a naturally occurring molecule that declines with age, rejuvenates aging immune cells and improves vaccine protection in older adults. 


Study conducted at the University of Oxford in England. 

Immunity

Aging Guru Bryan Johnson’s Supplement List for 2026

Changes to Bryan Johnson’s latest supplement stack include taking NMN or NR six days a week, rather than seven, and eliminating the use of rapamycin.

(Bryan Johnson, who utilizes a continuously updated protocol to slow aging and optimize his body | Netflix)

Changes to Bryan Johnson’s updated 2026 supplement stack include taking NMN or NR six days a week instead of seven and removing rapamycin.

Aging &amp; Longevity

Harvard: Microbiome Depletion Rejuvenates the Aging Brain

Harvard researchers find that aged mice lacking gut bacteria exhibit a brain more like that of young mice. 

The Principal Investigator of the study, Dr. Lee Rubin (image: harvard.edu). 

Brain &amp; Neurons

The interventions that may help fix or reset circadian rhythms, which decline with age. 

A representation of Kairos, not to be confused with Kronos (original image: misel-trogir.com).

Human studies show that a higher intake of the naturally occurring molecule spermidine may prevent cognitive impairments and dementia while improving longevity. 


Search Result: Spermidine

Anti-Aging Spermidine Boosts Immune System, New Study Shows

Aging Guru Bryan Johnson’s Supplement List for 2026

New Harvard Study: Microbiome Depletion Rejuvenates the Aging Brain

Beyond Aligning Life with Light: Supplements that Counter Circadian Decline

Spermidine: A Promising Nutrient for Brain Health and Cognitive Aging