| Home-made bone broth (240ml) |
~2.5–5g | Highly variable depending on bones used and cooking time |
| Pork skin |
~3–5g | One of the richest food sources; used in traditional gelatine |
| Beef (raw) |
~2–3g | Rich in Types I and III; higher in connective tissue cuts |
| Chicken skin/cartilage |
~1–4g | Particularly rich in Type II collagen around cartilage |
| Fish (skin-on, cooked) |
~0.5–2g | Marine source of Type I; higher in oily fish |
| Egg whites |
~0.5g | Contains proline, a key precursor amino acid for collagen |
| Red and yellow peppers |
High vitamin C | Essential for collagen synthesis — not a direct source |
| Citrus fruits |
High vitamin C | Supports collagen production via vitamin C co-factor activity |
| Plant foods |
None | Some provide precursor amino acids; no collagen directly |
