A tryptophan-rich milk protein that, taken in the evening, reliably raises the tryptophan reaching the brain to make serotonin and melatonin. Benefits for sleep, mood, and thinking are clearest in poor sleepers and stress-sensitive people, and modest elsewhere. Generally well tolerated, but a major milk allergen. Promising yet genuinely uncertain for the right person. (Full Review)
| Marker | Target | Why |
|---|---|---|
| eGFR | >90 mL/min/1.73m² | Confirms kidneys tolerate added protein load |
| Fasting glucose | 70–85 mg/dL | Tracks metabolic goals and glycemic response |
| HbA1c | <5.4% | Reflects 3-month average blood sugar |
| hs-CRP | <1.0 mg/L | General marker of systemic inflammation |
Cadence: Baseline before starting; reassess sleep and mood at ~2 weeks; recheck blood markers at 8–12 weeks, then every 6–12 months if use continues