Chondroitin for osteoarthritis

Singh JA, Noorbaloochi S, MacDonald R, Maxwell LJ · Cochrane Database of Systematic Reviews

The most trustworthy numbers in the chondroitin literature, and they are small. On the highest-quality node — WOMAC minimal clinically important improvement, level of evidence HIGH, risk of bias LOW — 53 of 100 on chondroitin achieved a 20% pain reduction against 47 of 100 on placebo, an absolute difference of 6%. Loss of minimum joint space width was 4.7% less than placebo (also HIGH quality, LOW risk of bias). Short-term pain showed a 10% absolute risk difference but with I-squared of 70% and low-quality evidence. Serious adverse events were lower than placebo.

Population

43 randomized trials, 4962 participants on chondroitin and 4148 on placebo or another control, mostly knee osteoarthritis

Intervention

Oral chondroitin, alone or combined

Comparator

Placebo, NSAIDs, analgesics or glucosamine

Limitations

The authors' central caveat: benefits 'were uncertain when we limited data to studies with appropriate allocation concealment, or large samples (>200), or studies without pharmaceutical funding'. High heterogeneity throughout. All trials used pharmaceutical-grade chondroitin at 800-1200 mg/day — nothing here transfers to chondroitin delivered in food.