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    Metabolic Health IngredientsNatural

    4-HIL Fenugreek

    Also known as: 4-hydroxyisoleucine, Fenfuro, 4-HIL

    Non-protein amino acid that selectively augments glucose-stimulated insulin secretion from pancreatic beta cells via direct effect on the islets.

    Last reviewed: 2026-06-23 · 1 indexed study

    Evidence Score
    48/100
    Glucose disposalInsulin sensitisationBody composition
    Data Completeness3/4 · 75%
    Evidence ScoreDosageSafetyLinked Studies

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    Overview

    4-Hydroxyisoleucine is an amino acid extracted from fenugreek seeds that enhances glucose-stimulated insulin secretion and improves nutrient partitioning.

    Mechanism & Function

    Mechanism of Action

    Glucose-dependent insulinotropic action improves glucose disposal post-meal without baseline hypoglycaemia risk.

    Physiological Role

    Used as a nutrient partitioner in bodybuilding stacks and metabolic health formulas; clinical data is emerging.

    Primary Pathways

    Beta-cell K-ATP channel modulationGlucose-dependent insulin secretionInsulin sensitisation

    Performance / Health Relevance

    Preclinical data are strong; human RCTs are limited but positive on glycaemic endpoints.

    Evidence Review

    Overall48/100
    Human Clinical42/100
    Meta-AnalysisN/A

    No meta-analyses or systematic reviews indexed for this ingredient yet.

    Mechanistic80/100
    Real-World50/100
    Safety80/100

    Dimensions marked N/A have no indexed evidence of that class. They are shown as unavailable rather than scored.

    Practical Use & Dosage

    Minimum Effective Dose
    500 mg
    Optimal Range
    1000–2000 mg/day with meals
    Upper / Caution Level
    ~3000 mg/day
    Timing
    Pre-carb meal
    Best Format
    Capsule, powder
    Bioavailability
    Moderate.
    Absorption Considerations
    Standard amino acid intestinal transport.

    Safety & Interactions

    Side Effects

    • •Mild GI upset

    Contraindications

    • Hypoglycaemia
    • Type 1 diabetes

    Drug Interactions

    • •Insulin
    • •Sulfonylureas
    • •Other antidiabetics

    Who Should Avoid

    • •Pregnancy

    Monitoring

    Blood glucose if diabetic.

    Frequently Asked Questions

    Auto-generated from indexed evidence — dosage, safety, interactions, and more.

    When is 4-HIL Fenugreek typically used or indicated?

    4-HIL Fenugreek is most commonly used for: Glucose disposal, Insulin sensitisation, Body composition. Used as a nutrient partitioner in bodybuilding stacks and metabolic health formulas; clinical data is emerging.

    How does 4-HIL Fenugreek work?

    Glucose-dependent insulinotropic action improves glucose disposal post-meal without baseline hypoglycaemia risk.

    What is the recommended dose of 4-HIL Fenugreek?

    The optimal range is 1000–2000 mg/day with meals. with a minimum effective dose of 500 mg. Best taken: Pre-carb meal. Upper / caution level: ~3000 mg/day.

    What are the side effects of 4-HIL Fenugreek?

    Reported side effects include: Mild GI upset. Monitoring: Blood glucose if diabetic.

    Does 4-HIL Fenugreek interact with medications?

    Known or theoretical interactions: Insulin; Sulfonylureas; and Other antidiabetics. Always check with a clinician before combining with prescription medication.

    Who should avoid 4-HIL Fenugreek?

    4-HIL Fenugreek is generally not recommended for: Pregnancy; Hypoglycaemia; and Type 1 diabetes.

    How strong is the evidence for 4-HIL Fenugreek?

    Evidence level: Limited (overall score 48/100), based on 1 indexed study on SuppIndex.

    Research & References (1)

    4-Hydroxyisoleucine from fenugreek on insulin sensitivity

    RCT2009Moderate
    PubMed

    Significant reduction in HbA1c and fasting glucose vs placebo.

    Trademark Ingredients

    Fenfuro®

    Manufacturer:

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    Research Overview

    Limited Evidence
    1Total Studies
    1Human Trials
    0Meta-Analyses
    2009Latest Study
    0Animal / In Vitro
    0Athlete Studies
    Primary data sourceClinical Patients
    Pooled evidence (meta-analysis / systematic review)No

    Cite this ingredient

    One-click citation export in APA, MLA, Chicago, BibTeX, or HTML. The URL below is stable and safe to link.

    Stable URL

    https://thesuppindex.com/ingredients/4-hil-fenugreek

    SuppIndex. (2026). 4-HIL Fenugreek: Evidence summary, dosage and clinical studies. Retrieved October 16, 2026, from https://thesuppindex.com/ingredients/4-hil-fenugreek

    Based on 1 indexed studies · Evidence level: Limited.

    Goal Ratings

    Metabolic Health
    Muscle Gain
    Fat Loss

    Stack Compatibility

    Pair with berberine, chromium, dihydroberberine for glucose disposal stack.

    BerberineChromiumDihydroberberine