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Leucine

17 benefits mapped to clinical evidence across supplements.

Serves the goals:Bone & JointCognitionFitnessHair & SkinImmune Support

Benefit Evidence

Muscle growth
Strong

MPS + leucine

Muscle size/gain +

3,420 people
Body composition
Strong

+lean mass, body weight

-muscle loss, protein breakdown

3,421 people
Healthy aging
Strong

Muscle gain + performance

Mortality/cognition benefits

-

6,625 people
Illness recovery
Strong

Anabolism + recovery

Less catabolism, shorter stay

BCAA/leucine support healing

1,879 people
Metabolism
Strong

Glucose/insulin ↓

Liver fat/IR ↓

4,453 people
Strength
Strong

Strength +5-15%

Strength +20 kg

1,773 people
Blood sugar
Moderate

↑ insulin, ↓ glucose

↓ insulin resistance

699 people
Exercise recovery
Moderate

MPS recovery +30-145%

Less breakdown/soreness

568 people
Workout performance
Moderate

MPS + performance

Strength + recovery

623 people
Immune support
Moderate

Immune markers +

Inflammation down, immunity up

362 people
Fat burn
Moderate

Fat loss +4.7 kg

Fat oxidation +33.6 g/d

248 people
Endurance
Moderate

Endurance +18.1 m

Muscle preservation +1,019 g

380 people
Skin repair
Moderate

Protein balance + synthesis

Wound repair + collagen

340 people
Appetite suppression
Weak

Leucine/AA ↑ satiety, CCK

Whey/BCAA ~13% intake ↓

106 people
Bone health
Weak

Vitamin D/PTH: +2% BMD

Leucine EAA: BMC preserved

440 people
Focus & concentration
Weak

Cognition +10.6%

Attention/reaction time

Protein synthesis

71 people
Muscle soreness
Weak

Reduced soreness; no detail

Lower soreness, +5% strength

41 people

Similar by evidence

Supplements the same benefits carry qualifying findings for — a fact about the evidence graph, not a recommendation to swap.

Essential Amino Acids

Shares 12 benefits: appetite suppression, body composition, endurance, focus & concentration

L-Carnitine

Shares 10 benefits: blood sugar, endurance, exercise recovery, fat burn

Whey Protein

Shares 10 benefits: appetite suppression, body composition, bone health, exercise recovery

HMB

Shares 10 benefits: body composition, bone health, endurance, exercise recovery

Creatine

Shares 9 benefits: blood sugar, bone health, endurance, exercise recovery

Urolithin A

Shares 9 benefits: endurance, exercise recovery, focus & concentration, healthy aging

Products with Leucine

Search all

108 products whose verified label declares Leucine — not every bottle that mentions it in a title.

Garden of Life

Garden of Life Organic Vegan Protein Powder, Plant Based & BCAAs

Includes 0g Added Sugars 0 g ¡ Vitamin D 10 mcg ¡ Calcium 30 mg +53 more

$29.06Pea

DRFOSTER

DRFOSTER Probiotics for Men Digestive Health, 120 Billion CFU

120 Billion CFUs Men's Probiotic Complex 500 mg ¡ BacĹllus coagulans ¡ Bacillus subtills +49 more

$17.99Probiotics

GU Energy

GU Energy Original Sports Nutrition Energy Gel, Vanilla Bean

Includes 7g Added Sugars ¡ GU Amino Acid Blend 450 mg ¡ L-Leucine +3 more

$37.36Chews & Gels

Optimum Nutrition

Optimum Nutrition BCAA Capsules, Keto Friendly, 1000mg, 200 Ct

L-Leucine, Micronized 500 mg ¡ L-Isoleucine, Micronized 250 mg ¡ L-Valine, Micronized 250 mg

$21.99BCAAs

Optimum Nutrition

Optimum Nutrition BCAA Capsules, Keto Friendly, 1000mg, 400 Ct

L-Leucine 500 mg ¡ L-Isoleucine 250 mg ¡ L-Valine 250 mg

$38.99BCAAs

Beverly International

Beverly International UMP Protein Powder, Vanilla, 32.8 oz

Calcium 350 mg ¡ Magnesium 120 mg ¡ Ultimate Protein System Blend 22.4 g +10 more

$46.95Blends

Being studied right now

Recruiting clinical trials registered on ClinicalTrials.gov. A trial in progress has no result yet — this is what the field is asking, not what it found.

Skeletal Muscle Adaptations to Peptide-Supplemented Resistance Exercise TrainingLeucine ¡ Supplement, Resistance Training Adaptation ¡ 24 participants planned ¡ ClinicalTrials.govRecruitingLeucine Requirements in School-Age ChildrenLeucine ¡ Nutrient Intake ¡ 7 participants planned ¡ ClinicalTrials.govRecruitingLeucine Requirements During PregnancyLeucine ¡ Pregnancy, Dietary Analysis, Protein ¡ 40 participants planned ¡ ClinicalTrials.govRecruiting