Read the label. We'll wait.

A naturally occurring amino-sugar and one of the core raw materials the body uses to build and maintain cartilage — the smooth cushioning tissue on the ends of the bones inside a joint. We use the hydrochloride (HCl) form on purpose: gram for gram, glucosamine HCl carries more actual glucosamine than the sulfate salt, so 400 mg of HCl delivers more of the building block and no added salt load. It gives the fast-forming joints of a growing puppy a steady daily supply of the primary structural building block they're using to lay down healthy cartilage in real time.

Supported by: 400 mg per chew — printed on the label

A large structural molecule (a glycosaminoglycan) that is a natural component of cartilage and helps that cartilage hold water so it stays springy and resilient under load. We disclose the source — bovine — because 'chondroitin' with no origin is a red flag. It works shoulder-to-shoulder with glucosamine as a building block for new cartilage, and helps developing cartilage retain fluid so it cushions well while the joint matures.

Supported by: 300 mg per chew — source disclosed

A naturally occurring source of bioavailable sulfur — the mineral the body reaches for when it assembles the collagen in cartilage, tendons and ligaments. Sulfur is the quiet workhorse of connective tissue, and 250 mg is a real, usable amount rather than a label decoration. It supplies sulfur the growing body uses to build the collagen framework of joints and the soft tissue around them, supporting normal connective-tissue development.

Supported by: 250 mg per chew — no 'sulfur complex' vagueness

A whole-food marine ingredient (Perna canaliculus) from New Zealand's coastal waters that naturally contains glycosaminoglycans plus a rare omega-3 fatty acid (ETA) found in almost nothing else. This is the ingredient we're proudest to disclose — it brings a mobility-and-comfort profile ordinary fish oil can't match, and it's exactly the ingredient cheaper formulas leave out or under-dose. It delivers naturally occurring joint building blocks plus its unique ETA omega-3 for broad daily mobility and comfort support across the long months a big dog spends growing.

Supported by: 250 mg per chew — a full dose, printed

A cold-water marine oil rich in omega-3s (EPA and DHA) carried in phospholipid form. We chose krill over commodity fish oil because its omega-3s come phospholipid-bound and it naturally carries the antioxidant astaxanthin. It provides omega-3 fatty acids that support a normal, comfortable inflammatory balance as an active puppy grows and plays.

Supported by: 150 mg per chew — named, not an 'omega blend'

A water-soluble antioxidant vitamin that also acts as a cofactor the body needs to form collagen. Collagen is the scaffolding of cartilage and connective tissue, so 50 mg earns its place beside the structural actives — and we list the exact form. It acts as an antioxidant and a cofactor the body uses when forming the collagen scaffolding of developing joints.

Supported by: 50 mg per chew — exact form listed

A fat-soluble antioxidant vitamin. We use D-alpha tocopherol — the natural form — not the cheaper synthetic 'dl' version, and we say so on the panel. Its job here is purely antioxidant: helping protect cells from everyday oxidative stress. We make no claim beyond that.

Supported by: 25 IU per chew — natural form, stated

A naturally occurring molecule that is a key component of the synovial fluid which lubricates and cushions a healthy joint. It's a premium touch you rarely see in a puppy joint chew — and when brands do include it, the amount is often invisible. It supports smooth, cushioned movement day after day while the joint continues to mature.

Supported by: 15 mg per chew — disclosed, not implied

An essential trace mineral that acts as a cofactor in the enzymes the body uses to assemble cartilage and connective tissue. Small amount, real job: manganese is a required cofactor for building the glycosaminoglycans in cartilage, so even 2 mg belongs on the label — and we name the exact form rather than hiding it in an 'other ingredients' fog.

Supported by: 2 mg per chew — exact form named