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Head-to-head evidence comparison — which supplement is right for you?
White Willow Bark wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Mostly mechanism / observational
Top outcomes
Verdict
Likely helps
4 of 4 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both UC-II and White Willow Bark have evidence — compare verdict strength side-by-side.
40mg UC-II daily (providing ~10mg undenatured type II collagen)
any
Undenatured type II collagen (UC-II, 40mg)
120-240mg salicin daily (from standardized extract)
With meals, Divided doses
Standardized extract (15% salicin)
8-24 weeks
8-16 weeks
Throughout use
1-2 weeks
1-4 weeks
Efficacy and tolerability of an undenatured type II collagen supplement in modulating knee osteoarthritis symptoms: a multicenter randomized, double-blind, placebo-controlled study.
Nutr J (2016) · Rct · n=191
UC-II 40mg/day improved total WOMAC vs placebo over 180 days
Safety and efficacy of undenatured type II collagen in the treatment of osteoarthritis of the knee: a clinical trial.
Int J Med Sci (2009) · Rct · n=52
UC-II reduced WOMAC 33% vs 14% for glucosamine+chondroitin
Undenatured type II collagen (UC-II(R)) for joint support: a randomized, double-blind, placebo-controlled study in healthy volunteers.
J Int Soc Sports Nutr (2013) · Rct · n=55
Improved average knee extension range vs placebo
Efficacy and Safety of White Willow Bark (Salix alba) Extracts
Phytotherapy research : PTR (2015) · Systematic review
In recent years, various in vitro and animal studies have demonstrated that the anti-inflammatory activity of willow bark extract is associated with down regulation of the inflammatory mediators tumor necrosis factor-α and nuclear factor-kappa B.
A systematic review on the effectiveness of willow bark for musculoskeletal pain
Phytotherapy research : PTR (2009) · Systematic review
All studies investigated ethanolic extracts with daily doses up to 240 mg salicin over periods of up to six weeks.
Cochrane review: Herbal therapy for low back pain
Cochrane Database of Systematic Reviews (2006) · Systematic review · n=500
Moderate evidence of efficacy
Based on Cochrane review showing dose-response relationship with 240mg more effective than 120mg. Studies limited to 6 weeks duration. Requires salicin-standardized extract.
AI-estimated from published studies. Interpret as directional guidance.
White Willow Bark has a higher evidence score (6/10 vs 5/10) and wins in 2 of 3 categories.
For joint health & mobility, White Willow Bark has a higher relevance score (88 vs 65).
No known interactions between UC-II and White Willow Bark have been documented in our database. However, always consult a healthcare provider before combining supplements.