🟢 100/100

This product looks safe

  • No ingredients exceed tolerable upper intake levels
  • Limited research evidence available for ingredients
B Label Compliance Grade

Product Label

📸

Have a supplement label? Find it here.

Upload a photo of any supplement label to search our database of 92,312 products.

Label Data

12.49 Gram(s) Serving Size
30 Servings
Other Combinations Product Type
0% Evidence Coverage

Supplement Facts — Evidence Check

Calories
35 Calorie(s)
Total Carbohydrates
4 Gram(s) (1% DV)
Protein
5 Gram(s)
Sodium
10 mg (1% DV)
3 Gram(s)
📊 Market median: 17.4mg (161 products)
Median 17.4mg This product: 3mg
Fast-Acting Comfort Blend
250 mg
UC-II standardized Cartilage
40 mg
MBP
40 mg

Other Ingredients

Natural & Artificial flavors Citric Acid Malic Acid Soy Oil & Lecithin Blend Acesulfame Potassium Sucralose Beta-Carotene

Label Claims — Verification

Nutrient
All Other
Structure/Function
All Other (100% of products) Structure/Function (90% of products) Nutrient (56% of products)

Target Groups

Adult (18 - 50 Years) Gluten Free

Product Information

📋 Directions for Use

Directions: As a dietary supplement, mix 1 scoop (12.49 g) into 8 - 10 fl. oz. of cold water or your favorite beverage once a day.

Also consider adding TriFlex or TriFlex Fast-Acting, which include glucosamine and chondroitin.

⚠️ Warnings & Precautions

Keep out of reach of children.

Contains: Milk and soybeans.

Warning: Consult your physician prior to using this product if you are pregnant, nursing, taking medication, or have a medical condition.

Discontinue use two weeks prior to surgery.

🧪 Formulation Notes

Contains: Milk and soybeans.

Gluten free.

Healthy joints- Features a blend of Chinese skullcap root extract and cutch tree bark extract that is clinically shown to provide a 30% improvement in flexibility and 19% improvement in joint function. Also has UC-II and collagen peptides, collagens that are clinically studied to support joint health. Strong bones- Contains MBP, a protein complex derived from milk that has been clinically shown to support bone density. Lean muscle- Includes 3 grams of leucine to support muscle protein synthesis plus 5 grams of protein for lean muscle support.

Additional Information

In a 12 week multi-center, randomized, double-blind, placebo-controlled study of 60 adults, subjects taking 250 mg/day of the Fast-Acting Comfort Blend showed a significant 29.8% improvement in joint flexibility and a 19.4% improvement in joint function in 30 days compared to subjects on placebo.

Store in a cool, dry place.

Promotes joint health

With ingredients clinically proven to provide 30% improvement in flexibility and 19% improvement in joint function

Natural and artificial flavors

CODE 308555 KRG

Notice: Significant product settling may occur.

Gf Gluten free

Worried about maintaining your active lifestyle? Workouts wearing you down?

See the lifestyle insert for more information.

Product Details

UPC / SKU 0 48107 16555 0
DSLD Entry Date 2017-08-22
Product Type Other Combinations
Form Powder
Brand GNC TriFlex
DSLD ID 76848
Data Updated 2026-04-11

Research Evidence

8 Research Sources
45 Avg Quality Score
7 Clinical Trial
1 Meta Analysis
B Effects of Whey Protein, Leucine, and Vitamin D Supplementation in Patients with Sarcopenia: A Systematic Review and Meta-Analysis
Meta Analysis Nutrients 2023
C Leucine-enriched Branched-chain Amino Acid on Muscle Thickness, Interleukin-6, SOFA Score in Critical Illness
Clinical Trial ClinicalTrials.gov 2023
C The Effects of Leucine Metabolites in Performance, Body Composition and Biochemical Markers of Muscle Damage
Clinical Trial ClinicalTrials.gov 2017
C Can Supplemental Leucine Offset Disuse-induced Muscle Atrophy?
Clinical Trial ClinicalTrials.gov 2017
C Leucine Supplementation in Sarcopenic Older Individuals
Clinical Trial ClinicalTrials.gov 2019
C The Effect of Leucine on Carnitine Transport to Skeletal Muscle
Clinical Trial ClinicalTrials.gov 2016
C Hydrolyzed Casein and Whey Protein Supplementation and the Addition of Leucine to Induce Protein Anabolism in Malnourished COPD Patients
Clinical Trial ClinicalTrials.gov 2009
C Resistance Exercise Training and Amino Acid Leucine Supplementation in Frail Elderly Women
Clinical Trial ClinicalTrials.gov 2013
View all evidence for Leucine →

Compare Similar Products

View all Leucine products →