Spermidine
Wheat Germ Extract · SPD
The autophagy trigger hiding in aged cheese and wheat germ. One of the strongest dietary longevity signals we know of.
What is Spermidine?
Spermidine is a naturally-occurring polyamine found in all living cells — and in particularly high concentrations in aged cheese, wheat germ, soybeans, mushrooms, and fermented foods. Its claim to fame in longevity science is simple: it is one of the most potent natural inducers of autophagy, the cellular recycling process that clears damaged proteins and organelles.
Autophagy is widely considered one of the key mechanisms behind the benefits of fasting and caloric restriction. Spermidine triggers autophagy without requiring you to not eat. This has led researchers to call it a "caloric restriction mimetic" — you get some of the cellular cleaning benefits of fasting while still eating normally.
The epidemiological data is compelling: populations with higher dietary spermidine intake have lower cardiovascular mortality and potentially longer lifespans. An Austrian cohort study following 829 people for 20 years found that those in the highest third of spermidine intake had a 5-year reduction in mortality risk compared to the lowest third. That is a remarkably large effect for a single dietary factor.
How Does It Work?
Spermidine induces autophagy primarily by inhibiting the acetyltransferase EP300 (also known as p300). When EP300 is inhibited, key autophagy proteins become deacetylated, which activates the autophagic machinery. This triggers formation of autophagosomes — the cellular "garbage trucks" that engulf and recycle damaged components.
Additionally, spermidine has anti-inflammatory effects (suppresses NF-kB), supports mitochondrial function, protects against oxidative stress, and may preserve telomere length. It also has documented effects on the gut microbiome, increasing beneficial bacterial populations.
What Does The Research Say?
Strong clinical evidence from human trials.
Strong epidemiological and mechanistic evidence. The 20-year Austrian cohort study (2018, Madeo et al.) showed significant mortality reduction. Animal studies consistently show lifespan extension: 10-25% in mice, worms, and flies. Autophagy induction is confirmed in human cells.
Human clinical trials: A 2021 RCT showed spermidine supplementation improved memory performance in older adults at risk of dementia. A 2022 trial showed improved cardiovascular biomarkers. The data quality is genuinely good — this is not just mechanistic hand-waving, there are real human outcomes.
Reported Dosages
These are dosages reported in research literature and community reports. They are NOT medical recommendations. Always consult a healthcare professional.
Clinical trials: 1-6mg daily of supplemental spermidine.
Wheat germ extract: 1-2 tablespoons daily provides approximately 1-2mg.
Dedicated supplements: 1-3mg spermidine content, taken daily.
No cycling appears necessary.
Dietary sources: aged cheese, wheat germ, soy, mushrooms, peas.
Legal supplement worldwide.
Side Effects & Risks
Extremely well-tolerated. It is a normal dietary component that humans have consumed throughout evolution. Mild GI effects at very high doses. No significant adverse events in clinical trials. One of the safest longevity interventions available.
Legal Status by Country
Legal supplement/food. Widely available.
Legal supplement. GRAS status. Widely available.
Legal supplement/food. Novel food approved.
Legal supplement. Available over the counter.
Where to Buy Spermidine
Buy Spermidineon Amazon UK →Affiliate link — we may earn a small commission at no extra cost to you.
Important Disclaimer
This profile is for educational and research purposes only. It does not constitute medical advice. Spermidine may be regulated or illegal in your jurisdiction. Do not use any compound without consulting a qualified healthcare professional. StackPedia does not sell, supply, or promote the use of any controlled substance.