Glucosamine, especially glucosamine sulfate, is extracted from the shells of shellfish to make dietary supplements. A synthetic form is made in laboratories, also.
In this article, we explain what glucosamine is, why it is taken as a supplement, and whether there is scientific evidence to prove it is effective. We also discuss any side effects and warnings that come with glucosamine.
What is it?
Glucosamine is normally taken by mouth and comes in different forms, including:
- glucosamine sulfate
- glucosamine hydrochloride
Although similar, these variants can have different effects when used as dietary supplements.
In some dietary supplements, glucosamine may be combined with other ingredients, including chondroitin sulfate, MSM, or cartilage.
Chondroitin is a similar substance to glucosamine and is found naturally in joints, as well.
Glucosamine is vital for building cartilage. Cartilage is a flexible, tough connective tissue found in several parts of the body. This firm, rubbery tissue functions as padding at the ends of long bones where they meet joints.
As we age, cartilage can become less flexible and can steadily breakdown. There is some evidence that glucosamine might slow this process.
Some scientists believe it is the sulfur in glucosamine that is beneficial for cartilage health. Sulfur must be incorporated into cartilage to build and repair it. Naturally, glucosamine plays a role in the incorporation of sulfur into cartilage.
As people age, glucosamine levels fall. So, in time, this may play a role in joint deterioration.
Does glucosamine help with osteoarthritis?
Many people take glucosamine supplements for OA, and especially OA of the hip or knee.
Some studies suggest that glucosamine may have the following effects:
- Reduce osteoarthritis-related pain, stiffness, and swelling in the joints.
- Improve function in people with knee or hip osteoarthritis.
- Provide continued relief of symptoms for up to 3 months after someone stops treatment.