Autophagy is activated through at least three independent molecular pathways: (1) mTOR inhibition (rapamycin, fasting, quercetin), (2) AMPK activation (metformin, fasting, quercetin), and (3) EP300 inhibition (spermidine). Activating multiple pathways simultaneously produces super-additive autophagy induction. Adding senolytics (fisetin) clears the senescent cells that autophagy cannot eliminate.

What is the minimum effective spermidine stacking protocol?

For a simple starting stack: spermidine (2 mg/day) + fisetin (20 mg/kg, 2 days monthly). This covers autophagy maintenance + senolytic clearance — the two primary cellular aging mechanisms — with minimal cost and complexity.

Is rapamycin required for a complete spermidine stack?

Rapamycin is optional and requires physician supervision. The natural pathway stack (spermidine + quercetin + fasting) activates mTOR and AMPK pathways without rapamycin's immunosuppressive risk. Add rapamycin when natural approaches plateau.