Calculate spermidine dose by goal — autophagy / longevity, cognitive support, hair growth. Trial doses range from 1.2 mg (food intake) to 6 mg (supplement protocols). Wheat germ is the cheapest natural source; branded supplements offer convenience at premium price. Math, not medical advice.
Your goal
3 mg/day
Spermidine target
3
capsules of Primeadine
Food sources (spermidine per serving)
| Food | Serving | Spermidine (mg) |
|---|---|---|
| Wheat germ | 2 tbsp (15g) | ~3.5 mg |
| Natto (fermented soybeans) | 1 cup | ~7 mg |
| Aged cheese (cheddar, parmesan) | 1 oz / 30g | ~1-2 mg |
| Mushrooms (cooked) | 1 cup | ~1-2 mg |
| Mature peas | 1 cup | ~1.5 mg |
| Soybeans (mature) | 1 cup | ~2 mg |
| Pear (ripe) | 1 medium | ~0.5 mg |
| Apple | 1 medium | ~0.3 mg |
| Broccoli | 1 cup | ~0.5 mg |
| Average Western diet | daily | ~10-15 mg total (varies wildly) |
Trial reference
| Trial | Population | Dose | Outcome |
|---|---|---|---|
| Schwarz 2018 SmartAge | Older adults, n=85 | 1.2 mg/day (wheat germ) | Cognitive improvement at 12 months |
| Wirth 2019 RCT | Older adults SCD, n=30 | 1.2 mg/day (wheat germ extract) | Memory + biomarker improvements over 3 months |
| Rinaldi 2017 | Telogen effluvium, n=100 | Wheat germ extract orally + topical | Hair growth + density vs placebo at 90 days |
| Eisenberg 2016 (animals) | Mice / cardiac | Various | Extended lifespan; cardioprotection in animals |
| NORDIC trial (ongoing) | Older adults cognitive | 3.3 mg/day | Results pending |
The autophagy mechanism (and honest take)
- Spermidine induces autophagy (cellular self-cleaning) via mTOR-independent pathway. Strong cell-culture and animal data.
- Longevity claims rest on animal lifespan extension (Eisenberg 2016) — flies, worms, mice show extended lifespan with spermidine supplementation.
- Human trials are limited to cognitive (SmartAge), hair (Rinaldi), and observational dietary intake correlations.
- Dietary intake correlates with lower all-cause mortality in observational studies (Kiechl 2018) but causation unclear.
- Reasonable take: spermidine is plausible but less proven than other longevity interventions (caloric restriction, exercise, sleep). A modest add-on, not a miracle.
Fasting + spermidine synergy
- Both induce autophagy. Fasting raises endogenous spermidine + activates AMPK pathway.
- Combined approach theoretically amplifies autophagy signal — but no human RCT confirms this.
- Eating during fast window: wheat germ or spermidine supplement does technically break fasting (contains calories). Some longevity protocols allow it given the autophagy goal.
- For pure stack: take spermidine during eating window; fast to amplify the autophagy benefit on non-eating days.
Side effects and contraindications
- Generally very well-tolerated. Wheat germ has been consumed in normal diets for millennia.
- Wheat allergy / celiac: obviously avoid wheat germ. Use soy-based or extracted spermidine instead.
- Soy allergy / thyroid concerns: avoid soy-based natto / soy spermidine sources.
- Cancer: autophagy is a double-edged sword for cancer. Some research suggests autophagy can protect tumor cells during chemo. Consult oncologist if active cancer treatment.
- Pregnancy/breastfeeding: no specific safety data; defer to obstetrician.
- Drug interactions: none well-established. Theoretical interactions with autophagy modulators (rapamycin, metformin) — additive effect possible.
