{
  "slug": "bcaa",
  "name": "BCAA (Branched-Chain Amino Acids · Leucine + Isoleucine + Valine)",
  "alternate_names": [
    "Branched Chain Amino Acids",
    "BCAAs",
    "Leucine-Isoleucine-Valine 2:1:1"
  ],
  "mechanism": [
    "Leucine is the principal trigger of mTORC1 signalling, activating S6K1/4E-BP1 to upregulate skeletal-muscle protein synthesis",
    "Oxidised peripherally via branched-chain ketoacid dehydrogenase (BCKDH) rather than the liver, providing a muscle-localised amino-acid fuel/anaplerotic substrate during exercise",
    "Modulates the plasma BCAA:tryptophan ratio, hypothesised to attenuate central-fatigue serotonin synthesis (mechanistic)",
    "Supports nitrogen handling / ammonia disposal in muscle as an alternative to hepatic urea-cycle clearance"
  ],
  "target": [
    "mTORC1 / S6K1 / 4E-BP1 muscle-protein-synthesis axis",
    "Branched-chain ketoacid dehydrogenase (BCKDH)",
    "Plasma BCAA:tryptophan ratio (central-fatigue model)",
    "Exercise-induced muscle damage / soreness markers"
  ],
  "use_case": [
    "resistance-exercise muscle-protein-synthesis support research (leucine-driven)",
    "exercise-induced muscle soreness / recovery research context",
    "muscle-mass maintenance during energy restriction or in older adults research",
    "intra-/peri-workout amino-acid supplementation when whole-protein intake is not desired"
  ],
  "body_system": [
    "MUSCLE",
    "METABOLISM"
  ],
  "evidence_tier": "C",
  "evidence_anchor_pmid_count": 2,
  "dosage_range": "Common ergogenic supplementation: 5-20 g/day BCAA at a 2:1:1 leucine:isoleucine:valine ratio (≥2.5-3 g leucine per serving to approach the leucine threshold for MPS). Note: BCAA alone is inferior to a complete EAA/whole-protein dose for maximal muscle protein synthesis because the other essential amino acids become rate-limiting; standalone-BCAA ergogenic efficacy on performance/hypertrophy is contested in RCTs.",
  "safety_notes": "Generally well tolerated at typical supplemental doses; mild GI upset possible. Theoretical considerations at chronic high intakes include altered amino-acid balance and competition with tryptophan/aromatic amino acids. Caution in maple-syrup-urine disease (BCKDH defect) and in advanced liver/renal disease without medical supervision. Some cohort data associate elevated circulating BCAAs with insulin-resistance markers (association, not supplement-causation). Not intended to diagnose, treat, cure or prevent any disease.",
  "regulatory": {
    "fda": "Permitted dietary-supplement ingredient under DSHEA (structure/function claims with mandatory disclaimer); L-leucine/L-isoleucine/L-valine hold industry self-affirmed GRAS status (no individual FDA GRN), are usable for food fortification under the 21 CFR 172.320 amino-acid framework, and are permitted in infant formula (21 CFR 107.100). No FDA-authorized health claim.",
    "efsa": "Permitted for sale as a food-supplement ingredient under Directive 2002/46/EC; existing amino acids (not Novel Food). EFSA has issued NO authorized health claim for BCAA — exercise-performance, muscle and immune Article 13 claims were rejected (EFSA opinions 2010;1817 and 2011;2225).",
    "anvisa": "Permitted dietary-supplement ingredient in Brazil: L-leucine/L-isoleucine/L-valine listed in IN 28/2018 Anexo I (authorized amino-acid ingredients) and used within the sports-nutrition supplement framework (RDC 243/2018).",
    "cn": "Permitted nutrient-fortification ingredient under NMPA: branched-chain amino acids (L-leucine/isoleucine/valine) listed in GB 14880-2012 food-fortifier standard and allowed in sports-nutrition foods (GB 24154); no health-function claim without registration."
  },
  "regulatory_markets": [
    {
      "market": "US",
      "status": "DSHEA",
      "tier": "permitted"
    },
    {
      "market": "EU",
      "status": "2002/46/EC",
      "tier": "permitted"
    },
    {
      "market": "CN",
      "status": "NMPA",
      "tier": "permitted"
    },
    {
      "market": "BR",
      "status": "ANVISA",
      "tier": "permitted"
    }
  ],
  "authorized_claims": [],
  "ingredient_hub_url": "https://asxan.ai/ingredients/bcaa/",
  "related_goal_slugs": [
    "athletic-performance"
  ],
  "related_lifestyle_slugs": [
    "athletic-performance",
    "senior-60-plus"
  ],
  "last_evidence_review": "2026-06-21",
  "schema_version": "nc-public-v0.2",
  "api_version": "nc-public-v0.3",
  "_meta": {
    "last_evidence_review": "2026-06-21",
    "ip_axes_disclosed": {
      "public_axes": [
        "mechanism",
        "target",
        "use_case",
        "body_system",
        "evidence_tier",
        "dosage_range",
        "safety_notes",
        "regulatory",
        "authorized_claims"
      ],
      "ip_axes_not_exposed": [
        "proprietary_formula_ratios",
        "clinical_protocol_internals",
        "proprietary_research_compounds",
        "supplier_specific_grade_specifications",
        "unpublished_endpoint_data"
      ],
      "rationale": "asxan.ai surfaces the educational, evidence-tier-disclosed slice. Formula composition and clinical-protocol internals are intentionally outside this public surface."
    }
  }
}