Source: Examine.com — Leucine — ~2.5–5 g to reach the leucine 'threshold' that triggers muscle protein synthesis.
The most anabolic of the BCAAs — the amino acid that flips the muscle-building switch.
Activates mTOR once it crosses the 'leucine threshold' (~2.5–3 g).
Safe. Usually you're better off eating complete protein, which comes with leucine plus everything else muscle needs.
| Per serving | |
|---|---|
| Typical branded single-ingredient product | $0.42 |
| Bulk powder at the clinical dose (500g, $29.97) | $0.30 |
Buying bulk powder instead of a branded bottle saves about 28% per serving.
Bulk price: $29.97/500g →Educational only — not medical advice. Grades and clinical doses are computed from public labels against sourced research (citations on the main site); prices last verified 2026-07-21. Expensive Powder has no sponsors; bulk links may earn an affiliate commission, which never affects a grade. Talk to a clinician before starting any supplement.