Condroitin is a structural component of cartilage commonly used as a dietary supplement for osteoarthritis

that shares a similar story with glucosamine.

There's a large heterogeneity in outcomes, with the industry-funded studies showing a benefit

for symptomatic relief, and the non-industry-funded study showing no effect, with a small

effect size similar to glucosamine.

Considering just the largest best-run study, the benefit of condroin was found to be minimal or non-existent,

and its use therefore be discouraged.

Like glucosamine, the current American College of Rheumatology guidelines, strongly recommend

against the use of condroitin for knee or hip osteoarthritis, along with the American Academy

of Orthopedic Surgeons and Osteoarthritis Research Society

International, whereas the European Society for Clinical and Economic Aspects of Osterprocess,

osteoarthritis and muscle skeletal diseases again allow for the use of pharmaceutical-grade

prescription-only, chondroitin.

Condroitin is typically extracted from animal cartilage, shark fins, bovine chicken windpipes

or pig noses, and slaughterhouse supply chains are not known for their good manufacturing practices.

The lack of purity and presence of contaminants is blamed in part for the lack of consistent reproducibility.

A study of 32 condroitin supplements on the market found that only five contained the label

amount, and some contained none.

Terms like quality-tested or retail price were found to provide no basis for judging quality.

Some of the cheapest and the most expensive condroitin on the market contained less than 10%

actual condroitin.

When the National Institutes of Health set out to design the esteemed gait trial, the

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