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Flex

product on market Tablet or Pill Core Nutritionals Safety: 100/100
100/100

This product looks safe

  • No ingredients exceed tolerable upper intake levels
  • 46% of ingredients have research evidence
A Label Compliance Grade

What the Evidence Says

✨ AI-generated · Qwen 3.6 · methodology

Glucosamine and MSM provide moderate evidence for supporting joint health and reducing discomfort. Boswellia extract and vitamins C and D3 further contribute to cartilage maintenance and bone support. Overall, these ingredients are well-documented for their role in joint function.

AI-generated summary based on research evidence. Not medical advice.

Label

Product Label

Label for Flex
Open Full PDF View on NIH DSLD →
Details

Label Data

8 Tablet(s)
Serving Size
30
Servings
Other Combinations
Product Type
46%
Evidence Coverage
Ingredients

Supplement Facts — Evidence Check

Vitamin C
500 mg (833% DV)
1000 IU (250% DV)
1.7× RDA — within safe limits 608 studies (A:16, B:251)
Market median: 1000.0mg (1115 products) 24 studies (A:0, B:9)
MSM
1000 mg
Market median: 1000.0mg (2 products)
Market median: 375.0mg (171 products) 31 studies (A:1, B:14)
Market median: 600.0mg (79 products) 25 studies (A:0, B:6)
Cissus quadrangularis extract
800 mg
Market median: 450.0mg (254 products) 243 studies (A:0, B:100)
400 mg
Market median: 200.0mg (136 products) 3 studies — no high-quality reviews
Black Cherry extract
100 mg
Black Pepper extract
5 mg

Other Ingredients

Stearic Acid Croscarmellose Sodium Maltodextrin Silicon Dioxide Dicalcium Phosphate Magnesium Stearate Food Glaze micro fine Wax
Claims

Label Claims — Verification

Unverified All Other
Unverified Structure/Function
Info

Product Information

Directions for Use

Directions: Take 8 tablets daily with or without food.

Warnings & Precautions

Warning: This product is only intended for use in healthy adults 18 years of age or older.

Pregnant or nursing women should not use this product. Consult your healthcare provider before using this product, especially if you are taking any prescription, over the counter medication, dietary supplement product, or if you have any pre-existing medical condition including but not limited to: high or low blood pressure, cardiac arrhythmia, stroke, heart, liver, kidney or thyroid disease, seizure disorder, psychiatric disease, diabetes, difficulty urinating due to prostate enlargement or if you are taking a MAOI (Monoamine Oxidase Inhibitor) or any other medication.

Discontinue use and consult your health care professional if you experience adverse reaction to this product. Discontinue use 2 weeks prior to surgery. Do not exceed recommended serving. Do not use if safety seal is broken or missing.

Keep out of reach of children.

Allergen statement: Contains shellfish.

Formulation Notes

Gluten free

Allergen statement: Contains shellfish.

Additional Information

Core Flex is a complete joint, soft tissue, and overall health supplement. Key ingredients in Core Flex may: Maintain good health. Enhance connective tissue formation. Protect against the deterioration of cartilage. Be a factor in maintaining healthy cartilage and joint health.

Comprehensive joint formula

30 day supply Clinical servings

Manufactured in a U.S. cGMP facility. Made in the USA.

Metadata

Product Details

UPC / SKU8 50757 00108 5
DSLD Entry Date2018-11-21
Product TypeOther Combinations
FormTablet or Pill
BrandCore Nutritionals
DSLD ID183122
Data Updated2026-04-11
Research

Research Evidence

371
Research Sources
54
Avg Quality
148
Meta Analysis
82
Systematic Review
71
Rct
62
Clinical Trial
2
Regulatory Source
1
Cochrane Review
1
Narrative Review
1
Other
1
Openfda Safety
A Vitamin C supplementation in pregnancy
Meta Analysis The Cochrane database of systematic reviews 2015 PubMed DOI
A Vitamin C supplementation for the primary prevention of cardiovascular disease
Systematic Review The Cochrane database of systematic reviews 2017 PubMed DOI
A Vitamin C for preventing and treating the common cold
Meta Analysis The Cochrane database of systematic reviews 2013 PubMed DOI
A Vitamin C for preventing and treating pneumonia
Meta Analysis The Cochrane database of systematic reviews 2013 PubMed DOI
A Vitamin E supplementation in pregnancy
Meta Analysis The Cochrane database of systematic reviews 2015 PubMed DOI
A Vitamin C supplementation for prevention and treatment of pneumonia
Meta Analysis The Cochrane database of systematic reviews 2020 PubMed DOI
A Vitamin C supplementation for prevention and treatment of pneumonia
Systematic Review The Cochrane database of systematic reviews 2021 PubMed DOI
A Nutritional interventions for preventing and treating pressure ulcers
Meta Analysis The Cochrane database of systematic reviews 2024 PubMed DOI
A Does Vitamin C Supplementation Provide a Protective Effect in Periodontal Health? A Systematic Review and Meta-Analysis
Meta Analysis International journal of molecular sciences 2024 PubMed DOI
A Circulating vitamin C concentration and risk of cancers: a Mendelian randomization study
Meta Analysis BMC medicine 2021 PubMed DOI
View all evidence for Vitamin C →
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This product page is for informational purposes only and does not constitute medical advice. Always consult your healthcare provider before taking any supplement.