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Compound Deep-Dive
Tier 1: MainstreamA potent trigger for muscle synthesis, but redundant if your protein intake is already high.
L-Leucine
Leucine2-Amino-4-methylpentanoic acid
The master anabolic switch.
Hype Risk
4/10
Noticeability
3/10
Evidence Tier
Strong
Cost / Month
~$15
Redundant with protein
What it's actually good for
Energy: neutralFocus: neutralSleep: neutralLongevity: neutralMood: neutralImmunity: neutral
How it works
L-Leucine is the primary branched-chain amino acid responsible for triggering muscle protein synthesis via the mTOR pathway. While highly effective at initiating the anabolic process, its impact on long-term muscle growth depends on the presence of other essential amino acids.
Activates the mechanistic target of rapamycin (mTOR) complex 1, which serves as a master regulator of protein synthesis and cell growth.
Safety
- Generally recognized as safe at supplemental doses.
- May lower blood glucose in some individuals.
- High doses may interfere with B-vitamin absorption over long periods.
The full StackRoast report adds
- The exact dose, timing, and effective range to actually run it at
- Where people go wrong with it — the dose-creep and timing traps
- What L-Leucine clashes with or duplicates in your stack
- Which brands are actually worth buying
Community Reality Check
Distilled from 850 threads
Community Reality Check
Distilled from 850 threadsConfidence: high
What users report
- Muscle preservation during cut
- Improved recovery
- Cheap anabolic trigger
The catch
- Terrible taste
- Poor solubility
- Redundant with high protein
Side effects reported
- Nausea on empty stomach
https://www.reddit.com/r/Supplementshttps://www.reddit.com/r/bodybuilding
The Receipts
8 sources— studies, videos & links
The Receipts
8 sources— studies, videos & linksVideos
Papers
Creators
Clinical Sources
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