Collagen type III

Tier 3 — weak evidence · Skin · Blood vessels · Gut lining

Found alongside type I collagen in skin, blood vessels, and gut lining. Most collagen supplements are predominantly type I. However, your body breaks all ingested collagen into the same amino acids regardless of type and reassembles them as needed. The type distinction in oral supplements is largely a marketing claim.

Dose: 5–10 g/day; body breaks down all collagen types into amino acids — type distinction is likely irrelevant orally