The following is a summary of Dr. Gray's presentation on selecting joint supplements, part of the SmartPak GetSmart series.

Horses can experience improved joint health with appropriate supplementation whether they are old or young, in heavy training or used recreationally, recovering from a joint injury, or just experiencing normal wear and tear. The three main ingredients in joint supplements--glucosamine, chondroitin sulfate, and hyaluronic acid--must be selected with care to ensure they are safe and effective.

Glucosamine is the building block of chondroitin sulfate, a specific type of polysulfated glycosaminoglycan (GAG). Not only does glucosamine increase production of new GAGs and therefore new cartilage, it also inhibits enzymes that break down cartilage.

Chondroitin sulfate is made by chondrocytes, living cells inside cartilage. A building block of the much larger proteoglycan molecule, chrondroitin sulfate also stimulates production of new cartilage while inhibiting enzymes that break down cartilage. A synergistic effect has been seen with the combination of chondroitin sulfate and glucosamine.

Hyaluronic acid is a nonsulfated glycosaminoglycan made in two places: chondrocyte cells in cartilage and synoviocyte cells in joint lining. It is an integral part of both joint cartilage and joint fluid, providing lubrication between surfaces. Hyaluronic acid is a long, chain-like molecule to which proteoglycan attaches.

When selecting a joint supplement, first evaluate the manufacturer then examine the product label. Choose companies that:

• Provide a guaranteed analysis, listing minimum amounts of active ingredients
• List their product's complete ingredients on the label
• Have performed independent research on their product and are willing to share it
• Have a reputation to protect and aren't willing to risk everything for a quick buck
• Don't make bold claims on the label about curing or treating disease