L-Leucine

Safe OtherNatural

L-Leucine is a naturally derived other used in dietary supplements. Safety rating: Safe. It is widely considered safe at typical supplement doses. Found in 20 supplements in the GoodSupp database. L-Leucine is an essential branched-chain amino acid.

20 Products use this
Safe Safety rating
Other Category
Yes Natural origin

Safety Verdict: Safe

This ingredient is rated safe for use in dietary supplements.

What is L-Leucine?

L-Leucine is an essential branched-chain amino acid.

Common Names L-Leucine
Type Other
Origin Natural / Plant-derived
Safety Rating Safe

Why is L-Leucine used in supplements?

It is included for its potential muscle-building and recovery benefits.

Role in supplements: Other — serves a functional role in supplement formulation.

Should you be concerned about L-Leucine?

No. L-Leucine is widely regarded as safe for use in dietary supplements at typical levels. It has a long history of use and is accepted by major regulatory bodies.

No action needed. This ingredient is safe at amounts used in supplements.

Top-rated products containing L-Leucine

These 20 highest-scoring supplements in our database use L-Leucine.

California Gold Nutrition Beauty, Menopause Support with Angelica gigas, Cynanchum wilfordii, Phlomis umbrosa and L-Leucine, 30 Veggie Capsules
California Gold Nutrition Beauty, Menopause Support with Angelica gigas, Cynanchum wilfordii, Phlomis umbrosa and L-Leucine, 30 Veggie Capsules
Product 100 Brand N/A
Allergy Research Group QuatreActiv® Folate, 90 Vegetarian Capsules (833 mcg per Capsule)
Allergy Research Group QuatreActiv® Folate, 90 Vegetarian Capsules (833 mcg per Capsule)
Product 100 Brand N/A
Life Extension Resveratrol Elite™, 30 Vegetarian Capsules
Life Extension Resveratrol Elite™, 30 Vegetarian Capsules
Product 100 Brand N/A
Doctor's Best Benfotiamine 300 with BenfoPure™, 300 mg, 60 Veggie Caps
Doctor's Best Benfotiamine 300 with BenfoPure™, 300 mg, 60 Veggie Caps
Product 100 Brand N/A
Seeking Health Lithium Orotate, 5 mg, 100 Vegetarian Capsules
Seeking Health Lithium Orotate, 5 mg, 100 Vegetarian Capsules
Product 100 Brand N/A
Swanson R-5-P, Riboflavin-5-Phosphate, 50 mg, 60 Veggie Caps
Swanson R-5-P, Riboflavin-5-Phosphate, 50 mg, 60 Veggie Caps
Product 100 Brand N/A
Seeking Health Molybdenum, 500 mcg, 90 Capsules
Seeking Health Molybdenum, 500 mcg, 90 Capsules
Product 100 Brand N/A
Doctor's Best L-Tyrosine, 500 mg, 120 Veggie Caps
Doctor's Best L-Tyrosine, 500 mg, 120 Veggie Caps
Product 100 Brand N/A
Swanson Full Spectrum Mucuna Pruriens, 400 mg, 60 Capsules
Swanson Full Spectrum Mucuna Pruriens, 400 mg, 60 Capsules
Product 100 Brand N/A
Swanson Albion® Molybdenum, 400 mcg, 60 Veggie Caps
Swanson Albion® Molybdenum, 400 mcg, 60 Veggie Caps
Product 100 Brand N/A
California Gold Nutrition Beauty, Menopause Support with Angelica gigas, Cynanchum wilfordii, Phlomis umbrosa and L-Leucine, 90 Veggie Capsules
California Gold Nutrition Beauty, Menopause Support with Angelica gigas, Cynanchum wilfordii, Phlomis umbrosa and L-Leucine, 90 Veggie Capsules
Product 100 Brand N/A
Doctor's Best Menopause Spectrum®, 30 Veggie Caps
Doctor's Best Menopause Spectrum®, 30 Veggie Caps
Product 100 Brand N/A
Doctor's Best Benfotiamine with BenfoPure®, 150 mg, 360 Veggie Caps
Doctor's Best Benfotiamine with BenfoPure®, 150 mg, 360 Veggie Caps
Product 100 Brand N/A
Seeking Health Acetyl-L-Carnitine, 500 mg, 90 Capsules
Seeking Health Acetyl-L-Carnitine, 500 mg, 90 Capsules
Product 100 Brand N/A
NutriCology L-Methionine, 500 mg, 100 Vegetarian Capsules
NutriCology L-Methionine, 500 mg, 100 Vegetarian Capsules
Product 100 Brand N/A
Dr. Mercola Liposomal Hyaluronic Acid, 100 mg, 30 Capsules
Dr. Mercola Liposomal Hyaluronic Acid, 100 mg, 30 Capsules
Product 100 Brand N/A
Health Thru Nutrition Magnesium Bisglycinate, 200 mg, 120 Tablets
Health Thru Nutrition Magnesium Bisglycinate, 200 mg, 120 Tablets
Product 100 Brand N/A
NutriCology QuatreActiv™ Folate, 90 Vegetarian Capsules
NutriCology QuatreActiv™ Folate, 90 Vegetarian Capsules
Product 100 Brand N/A
NutriCology L-Lysine, 100 Capsules
NutriCology L-Lysine, 100 Capsules
Product 100 Brand N/A
Allergy Research Group L-Methionine, 500 mg, 100 Capsules
Allergy Research Group L-Methionine, 500 mg, 100 Capsules
Product 100 Brand N/A
Related Ingredients
Frequently Asked Questions
Is L-Leucine safe in supplements?

Yes. L-Leucine is rated safe for use in dietary supplements at typical levels. This rating is based on regulatory assessments, published safety research, and its long history of use in the supplement industry. It is widely accepted by major regulatory bodies including the FDA and EFSA. In GoodSupp's database, 20 products contain this ingredient. Consult your healthcare provider if you have specific concerns.

What is L-Leucine and why is it in my supplement?

L-Leucine is an essential branched-chain amino acid. It appears in 20 products in the GoodSupp database.

Is L-Leucine natural or synthetic?

L-Leucine is naturally derived, meaning it comes from natural sources such as plants, minerals, or animal products rather than being chemically synthesized. Natural-origin ingredients are preferred by many consumers, though it's important to note that 'natural' does not automatically mean 'safer' — safety depends on the specific substance, its purity, and the amount used. The safety rating assigned by GoodSupp is based on the ingredient's actual safety profile, not its origin.

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Disclaimer: GoodSupp provides independent supplement quality analysis for informational purposes only. Scores are generated algorithmically based on ingredient profiles, brand certifications, and public records. This is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Product data is sourced from manufacturer labels and public databases. GoodSupp is not affiliated with any supplement brand.