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Glucosamine & chondroitin

Glucosamine sulfate; chondroitin sulfate

Supplements. Modern nutrition.

Also called Glucosamine HCl, Chondroitin, Chondroitin sulfate

Pinyin: ān jī pú táo táng

Spanish: Glucosamina y condroitina

Shellfish-based; may raise sugar

Building blocks of cartilage, sold as supplements for knee and joint pain.

Did you know? Most glucosamine is made from the chitin in shrimp and crab shells, not from plants.

What it may help, and how strong the proof is

Joint pain & arthritis. A large US trial (GAIT) found no clear pain relief overall, but people with moderate to severe knee pain did better. Results across trials are mixed.
Early proof
Inflammation. Lab studies suggest an anti-inflammatory effect. Human proof for this is weak.
Traditional proof

Parts of the body

Joints, Immune system

Traditional use

Glucosamine and chondroitin have no traditional herbal use. They became popular as joint supplements in the 1990s.

How it is classified

Herbal actions: Analgesic, Anti-inflammatory. Energy: neutral.

How people take it

The GAIT trial used 1,500 mg of glucosamine and 1,200 mg of chondroitin a day. Results take weeks to months to show.

Capsule, tablet and powder.

Where to get it

Glucosamine is usually made from shellfish shells, and some versions come from corn or fungus. Chondroitin is usually from animal cartilage. Both are sold as capsules, powders and joint blends.

Be careful

Common side effects are stomach upset, heartburn and headache. Shellfish-based products can cause reactions in people with shellfish allergies. Some studies suggest glucosamine can raise blood sugar, and chondroitin may add to warfarin's blood-thinning effect in case reports.

Avoid if: shellfish allergy; diabetes.

Mixing with other things

Works well together
Often sold together in joint blends. The combined benefit is not well proven.
Works well together
Boswellia and glucosamine are both sold in joint formulas. Evidence for the mix is limited.
Use caution
Blood thinners (warfarin, Eliquis, Xarelto, Plavix, daily aspirin)
Chondroitin may raise INR and bleeding risk with warfarin, based on case reports.
Use caution
Diabetes medicine (metformin, insulin, glipizide, Ozempic)
May raise blood sugar in some people. Check levels if you take diabetes medicines.

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Adds up with others that may lower blood sugar: , , , , , , , , , , , , , and 39 more.

The honest take

The best large trial found little overall pain relief, and only people with more severe knee pain seemed to benefit. Product quality varies. Exercise, weight loss and physical therapy have stronger proof for knee osteoarthritis.