Epigenetic reprogramming substrate vs direct autophagy inducer
What this is
Head-to-head evidence table: Ca-AKG (Calcium Alpha-Ketoglutarate) vs Spermidine (compound).
Why it matters
Ca-AKG and spermidine are both emerging longevity compounds with striking epigenetic and autophagy data — but they operate at entirely different nodes. Ca-AKG is a TET DNA demethylase cofactor: it supplies the substrate TET enzymes need to remove methyl groups from aging DNA, potentially reversing epigenetic drift. Spermidine inhibits EP300 acetyltransferase, triggering autophagy flux that clears damaged organelles and proteins. Together they address the two biggest non-NAD+ longevity nodes: epigenetic age and proteostasis.
What to do next
Use the verdict row to pick a primary compound, then open both deep-dives and /shop verification checklists.
Ca-AKG and spermidine are both emerging longevity compounds with striking epigenetic and autophagy data — but they operate at entirely different nodes. Ca-AKG is a TET DNA demethylase cofactor: it supplies the substrate TET enzymes need to remove methyl groups from aging DNA, potentially reversing epigenetic drift. Spermidine inhibits EP300 acetyltransferase, triggering autophagy flux that clears damaged organelles and proteins. Together they address the two biggest non-NAD+ longevity nodes: epigenetic age and proteostasis.
Epigenetic clock reversal
Ca-AKG (Calcium Alpha-Ketoglutarate)
Rejuvant trial (Demidenko 2021): −7.5 years biological age (Horvath clock) in 42 adults over 7 months
Spermidine
Indirect — autophagy improves proteostasis which correlates with slower epigenetic drift
Autophagy induction
Ca-AKG (Calcium Alpha-Ketoglutarate)
Indirect — AKG is an mTORC1 suppressor; reduces mTOR signaling that blocks autophagy
Spermidine
Direct — EP300 inhibition mimics caloric restriction autophagy trigger at mg-level dosing
Mechanism type
Upstream epigenetic (Ca-AKG) vs cytoplasmic organelle renewal (spermidine) — orthogonal
Ca-AKG (Calcium Alpha-Ketoglutarate)
TET cofactor → DNA demethylation → epigenetic reprogramming
Spermidine
EP300 inhibitor → autophagic flux → proteostasis + immune renewal
mTOR modulation
Ca-AKG is a credible mTOR longevity axis drug — distinct from rapamycin but overlapping
Ca-AKG (Calcium Alpha-Ketoglutarate)
Strong mTORC1 suppression — AKG competes at glutamine-sensing node
Spermidine
Indirect mTOR suppression via AMPK-related signaling
Human observational lifespan data
Ca-AKG (Calcium Alpha-Ketoglutarate)
No long-term lifespan cohort data yet
Spermidine
Kiechl 2018 (PMID: 29991564): higher dietary spermidine → 5yr lower mortality in n=829 cohort
Immune T-cell rejuvenation
Ca-AKG (Calcium Alpha-Ketoglutarate)
Not a primary mechanism
Spermidine
Phase II: spermidine restored T-cell memory responses in older adults
Cost
Ca-AKG (Calcium Alpha-Ketoglutarate)
Rejuvant/Ca-AKG: $50–80/month for 1 g/day
Spermidine
Spermidine: $40–70/month for standardized 1–2 mg/day; or dietary from wheat germ
Safety profile
Ca-AKG (Calcium Alpha-Ketoglutarate)
Well-tolerated in Rejuvant trial; AKG is endogenous metabolite
Spermidine
Excellent — endogenous polyamine; dietary equivalent dosing used in trials
TNiC verdict
Ca-AKG leads on epigenetic clock reversal evidence (Rejuvant trial: −8yr biological age). Spermidine leads on autophagy breadth, immune rejuvenation, and observational lifespan data. Stack both if budget allows — they are mechanistically orthogonal and naturally synergistic.
Choose Ca-AKG (Calcium Alpha-Ketoglutarate) when
Choose Spermidine when
Decided? Each verified pick matches the studied dose and form, and links straight to the manufacturer.
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