Leucine

Leucine carries a safety score of 3/5 and appears in 57 indexed US food products.

Safety score 60.0%

3/5 from FDA SAFFA + CSPI Chemical Cuisine

How common is vs other flagged additives?

Number of indexed products containing each of the most common flagged additives — Leucine highlighted.

Indexed products containing each flagged additive. Source: Open Food Facts ingredient lists × FDA SAFFA × CSPI Chemical Cuisine.

Caramel Coloring22612Red 4021595Yellow 518987Carrageenan17853Blue 116643Yellow 613560Sucralose10490Leucine57
Indexed products containing each flagged additive. Source: Open Food Facts ingredient lists × FDA SAFFA × CSPI Chemical Cuisine.
Safety Score
3/5

Safety Assessment

Leucine has a moderate safety profile (3/5). While approved for use, some studies or consumer advocacy groups have raised questions about certain aspects of this ingredient. Consumers who prefer caution may wish to limit intake.

What the Data Says About

Leucine currently appears in 57 products across the OpenFoodFacts catalog we index, which gives a concrete measure of its footprint on US grocery shelves. Our internal safety score of 3/5 synthesizes FDA Substances Added to Food (SAFFA) regulatory status with the Center for Science in the Public Interest (CSPI) Chemical Cuisine classification. These two frameworks capture different questions: regulators ask whether exposure at typical intake is acceptable, while consumer-advocacy groups examine cumulative dietary load and vulnerable-population risk.

Leucine serves one or more technical functions in food manufacturing — stabilization, flavor, preservation, or structural role — which explains its presence across multiple product categories in our database. Inspection and outbreak records frequently trace back to control failures around functional additives, whether through batch contamination, undisclosed substitutions, or labeling mismatches that trigger recall classifications by the FDA.

No specific concern flags are attached to Leucine in our current data snapshot beyond the regulatory and CSPI classifications above. That does not rule out individual sensitivity reactions, and anyone managing allergies, elimination diets, or chronic conditions should verify with a qualified healthcare professional before relying on population-level ratings.

Safety Profile at a Glance

Regulatory and safety classifications for Leucine
Source Classification Year
FDA SAFFA Not listed 2024
CSPI Chemical Cuisine Not rated 2024
PlainFoodSafe Score 3/5 2026
Product footprint 57 products OpenFoodFacts

FDA SAFFA database, CSPI Chemical Cuisine ratings, OpenFoodFacts product index. See methodology.

Products Containing

Showing 50 of 57 products

5-mthf 5 Mg Methylfolate
Thorne
100/100
Advanced Digestive Enzymes
Thorne
100/100
AMINOLEAN
RSP
100/100
Aquarius, soft drink
Aquarius
85/100
Arizona, energy drink, mucho mango
Arizona, Ferolito Vultaggio & Sons
100/100
Arizona, natural energy drink, watermelon
Arizona
100/100
BCAA Natural Grape
Sascha Fitness
100/100
BCAA Natural Lemon Lime
Sascha Fitness
100/100
BCAA Natural Mango Coconut
Sascha Fitness
100/100
BCAA Natural Pineapple
Sascha Fitness
100/100
BCAA Natural Watermelon
Sascha Fitness
100/100
Beef Collagen Peptides
Carnivore Aurelius
100/100
Chews, watermelon
Unknown
100/100
Complete plant protein, chocolate
Unknown
100/100
Complete Protein Shake Creamy Vanilla Bean
Plantfusion
100/100
Complete Protein Shake Creamy Vanilla Bean
Plantfusion
100/100
Complete Protein Shake Rich Chocolate
Plantfusion
100/100
Complete Protein Shake Rich Chocolate
Plantfusion
100/100
Complete Protein Shake Rich Chocolate
Plantfusion
100/100
Creamy Vanilla Bean Cardio Whey Protein Concentrate, Creamy Vanilla Bean
Cardiotabs
95/100
D-1,000
Thorne
100/100
Dr. Berg Veggie Solution
Unknown
100/100
Duncan hines, decadent cake mix, triple chocolate
Duncan Hines
95/100
EAA Essential Amino Acids
Xtend
70/100
Energy Gel
Advanced Food Concepts Inc.
100/100
Forza Whey Protein
Forzagen
85/100
Fury
Animal
85/100
Grass fed collagen peptides
Thrive market
100/100
Hydrolyzed Collagen Powder
Trader Joe's
100/100
Iron Bisglycinate
THORNE
100/100
Lemon Swish Protein Powder
Just Ingredients
100/100
Magtein Magnesium
The Vitamin Shoppe
100/100
Marine Collagen
MD Hair
100/100
Natural energy arnold palmer
Unknown
100/100
Nugenix
Unknown
100/100
Nuphoria cm Gold
Nuphoria
100/100
Plant Protein Golden Chai Latte Flavour
Botanika Blends
100/100
Plant Protein Organic Ingredients
Botanika Blends
100/100
Pre-Workout Clean Energy & Hydration Fuel Watermelon
Unknown
100/100
Premium Vegan Protein 7k+
Sport Line
100/100
Pure EAA
atplab
100/100
Raspberry Lemonade
Unknown
100/100
Raspberry lemonade energy drink mix, raspberry lemonade
Unknown
100/100
Recovery
Momentous
100/100
Rich Cocoa Cardio Whey Protein Concentrate, Rich Cocoa
Cardiotabs
100/100
Silk Collagen Lume
Elixir
100/100
sirius groom conditioner for dogs
Unknown
100/100
Stress Balance
Thorne
100/100
Theanine
Thorne
100/100
Think Magnesium L-threonate
KAL
100/100

Frequently Asked Questions

Is Leucine safe to eat?

Leucine has a safety score of 3/5. Always check with a healthcare provider if you have specific dietary concerns.

What products contain Leucine?

Leucine is found in 57 products in our database, spanning various food categories and brands.

What does Leucine do in food?

Leucine serves various technical functions in food manufacturing and processing.

Where does this ingredient safety data come from?

Safety data comes from the FDA's SAFFA (Substances Added to Food) database, CSPI (Center for Science in the Public Interest) ratings, and the OpenFoodFacts product database. Product counts reflect items cataloged in OpenFoodFacts.