What’s inside this formula?
Natural Factors’s FlexAble Glucosamine Sulfate — 500 mg is listed here in the glucosamine collection. This article looks at the selected 180 capsules pack, then puts its ingredients into context.
Each capsule has 667 mg stabilized glucosamine sulfate complex providing 500 mg glucosamine sulfate from shellfish. Sodium is below 0.5 mg and potassium below 100 mg per capsule.
Check the original label ↗Glucosamine occurs in cartilage-related biology and is sold in several chemical forms, often alongside chondroitin or other ingredients. Trials for knee osteoarthritis have produced inconsistent results. This makes the precise preparation important and means that a plausible cartilage-related mechanism cannot be turned into a promise that a supplement rebuilds a joint.
The pack details above come from the manufacturer. Ingredient research below does not establish the effects of this exact product or independently verify its contents.
Complex weight versus active amount
The 667 mg complex provides 500 mg glucosamine sulfate. Comparing 667 mg directly with another product’s active-glucosamine quantity would overstate its dose.
Low sodium does not mean mineral-free
The Canadian source reports less than 0.5 mg sodium but up to the stated limit of less than 100 mg potassium per capsule. The selected photographed pack has 180 capsules.
Diet and evidence limits
The adult label direction is one capsule three times daily with food. It is animal-derived; NCCIH notes uncertain osteoarthritis benefit and a warfarin-related bleeding concern for glucosamine/chondroitin.
Where might it be useful?
Possible symptom effects in selected studies
Some trials of particular preparations report less osteoarthritis pain, while others find no useful benefit.
A formulation-sensitive question
Results for prescription crystalline glucosamine sulfate should not automatically be assigned to other forms or mixed retail products.
What the research can — and cannot — tell us
NCCIH describes conflicting research and differing guideline recommendations. Several guidelines recommend against routine use, while others distinguish selected prescription preparations. There is no general proof of cartilage regrowth, and findings for glucosamine alone do not establish benefit for this exact branded formula or combination.
What deserves your attention?
Contains shellfish-derived glucosamine and gelatin. Discuss warfarin, diabetes, pregnancy or breastfeeding before use; seek review if joint symptoms worsen.
Suitability comes before strength
Glucosamine can increase warfarin’s effect and may affect blood glucose in some people. Check the source if avoiding shellfish-derived ingredients. Review persistent joint pain and all medicines before starting a supplement.
Dietary details for this product
Animal-derived The manufacturer identifies shellfish exoskeletons as the glucosamine source and gelatin in the capsule.
A dietary label and an allergy assessment answer different questions. Check every ingredient, the capsule or softgel materials and the allergen statement on the pack you receive. If you take medicines, have a health condition, are pregnant or are choosing for a child, discuss the full formula with a qualified clinician.
Make the comparison meaningful.
- Match the exact version.Look for Natural Factors · FlexAble Glucosamine Sulfate — 500 mg and the 180 capsules pack. A similar name or bottle can contain a different strength, blend or serving.
- Compare like with like.Read the serving size alongside the active ingredient amount. Capsule count, compound weight and total blend weight can describe different things. Use the label notes above to see what matters for this formula.
- Check the seller and final cost.Review seller identity, expiry, batch details and any Indian import information. Compare the final delivered price only after matching the formula. Prices and stock are checked on the retailer’s site.
Keep the label beside the decision.
Open the complete product profile for its source, dietary notes and available shopping destination.
Is this an endorsement or a medical recommendation?
No. This is an editorial guide to a selected product and its ingredient context. We have not independently tested this bottle or established a clinical benefit for this exact formula. A product’s inclusion is not a recommendation that everyone should take it.
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Read, check, decide.
Product label reviewed 2026-10-29. Ingredient context reviewed 2026-10-26. This article has not received independent clinical review. Packaging and formulas can change; the current pack takes precedence.
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