Comparison
Melatonin vs Spirulina
Melatonin
Pineal hormone regulating circadian rhythm. Low doses (0.3-1mg) often outperform higher doses for sleep.
Spirulina
Blue-green microalgae used as nutritional supplement. High protein, complete amino acids, phycocyanin antioxidant.
| Field | Melatonin | Spirulina |
|---|---|---|
| Category | neuroprotective | neuroprotective |
| Dose range | 0.3–3mg | 1000–5000mg |
| Half-life | 1h | — |
| Onset | 30min | — |
| Evidence | EVIDENCEA | EVIDENCEB |
| Safety | ●●●●● | ●●●●○ |
| Legal (US) | USOTC | USOTC |
| PubMed refs | 28000 | 2400 |
The comparison in plain English
Auto-generated from dataMelatonin and Spirulina are both in the neuroprotective category respectively. Melatonin Pineal hormone regulating circadian rhythm. Spirulina Blue-green microalgae used as nutritional supplement.
Bottom line
Melatonin (evidence A, safety 5/5) has a weaker evidence base than Spirulina (evidence B, safety 4/5). Melatonin has the slightly cleaner safety profile. For users new to either, the higher-evidence option is the safer first try.
Choose Melatonin if
Melatonin is the better fit when your goal aligns with its mechanism (Endogenous hormone produced by the pineal gland in response to darkness, signalling the circadian sleep window) and the dose range (0.3–3mg) suits your protocol. Half-life is 1h.
Choose Spirulina if
Spirulina is the better fit when your goal aligns with its mechanism (Provides complete protein with all essential amino acids) and the dose range (1000–5000mg) suits your protocol. Half-life is —h.