Glucosamine and chondroitin: what it is and how much people take

Glucosamine and chondroitin are building blocks and parts of cartilage. Studies have looked at knee osteoarthritis, with conflicting results. Studies have usually used 1,500 milligrams of glucosamine and 1,200 milligrams of chondroitin a day in the largest NIH trial. Glucosamine may raise blood sugar in some people.

Checked 28 September 2026 · Source: NCCIH (US National Institutes of Health) · Adults only

General information, not medical advice. Check with a doctor or pharmacist before taking a supplement, especially if you are pregnant or breastfeeding, take any medicine, or are under 18.

How much people take

What studies looked atStudies have looked at knee osteoarthritis, with conflicting results.
Amounts studies used1,500 milligrams of glucosamine and 1,200 milligrams of chondroitin a day in the largest NIH trial.
Official upper limitNone set

Cautions and interactions

Quick answers

What is glucosamine and chondroitin?
Glucosamine and chondroitin are building blocks and parts of cartilage.
What has glucosamine and chondroitin been studied for?
Studies have looked at knee osteoarthritis, with conflicting results.
How much glucosamine and chondroitin do studies use?
1,500 milligrams of glucosamine and 1,200 milligrams of chondroitin a day in the largest NIH trial.
Is glucosamine and chondroitin safe?
Glucosamine may raise blood sugar in some people. Both have been linked to bleeding with warfarin. Many glucosamine products are made from shellfish.

Sources

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