Supplement analysis backed by scientific evidence · PT

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Moderate evidenceJoints & skin

Undenatured Type II Collagen (UC-II)

A 40 mg daily dose of undenatured type II collagen improved knee osteoarthritis symptoms more than placebo — and more than glucosamine plus chondroitin — in a 180-day randomised trial. The evidence base is small and dominated by the ingredient manufacturer, so treat the effect size with caution.

What the science says

  • Knee osteoarthritis symptoms Moderate evidence

    In a multicentre RCT of 191 adults, 40 mg/day UC-II for 180 days reduced total WOMAC significantly more than placebo (p = 0.002) and more than glucosamine HCl 1500 mg + chondroitin 1200 mg (p = 0.04), with benefits across the pain, stiffness and function subscales.

  • Joint comfort and flexibility in healthy people Limited evidence

    Two small trials in exercisers and healthy adults with knee discomfort (roughly 55-100 participants each, 40 mg/day for 120-180 days) reported greater knee range of motion and longer time to exercise-induced discomfort. These are short, small and manufacturer-run.

  • Superiority to glucosamine and chondroitin Limited evidence

    The head-to-head advantage rests on a single trial, and the 2023 meta-analysis pooling undenatured collagen studies included only a few trials, several with author or funding links to the ingredient supplier. Independent replication is missing.

Dosage & safety

Studied dose40 mg/day of UC-II material, delivering approximately 10 mg of bioactive undenatured type II collagen. Usually taken once daily on an empty stomach or at bedtime. Trials ran 90-180 days; benefit accrues slowly.
SafetyWell tolerated in trials, with adverse event rates matching placebo; occasional mild gastrointestinal upset. Derived from chicken sternum cartilage, so avoid with poultry or chicken protein allergy. Do not confuse with hydrolysed collagen peptides — those are used at 10 g/day and work by a different, nutritive mechanism, and 40 mg of peptides would do nothing. The proposed mechanism is oral tolerance via gut-associated lymphoid tissue; there is no clinical signal of harm in autoimmune disease, but data in that population are absent. No known drug interactions.

Scientific references

Where to buy

Swanson Vitamins, UC-II® Standardized Collagen, 60 Capsules

View on iHerb

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