Collagen peptides

What it is

Collagen peptides are short chains of amino acids made by breaking down animal collagen into fragments small enough to be absorbed from the gut. Once absorbed, they enter the body's general amino acid pool and supply the building blocks, notably glycine and proline, that connective tissue draws on. They are taken as a food supplement in the context of joint and skin support.

Used for

• Joints
• Skin

What to know while taking it

Timing is flexible: the peptides can be taken with a meal or between meals, and no particular food is needed for absorption. The amino acid profile is unbalanced and low in the essential amino acids, so collagen does not count as a complete protein source and should not displace ordinary dietary protein. It is a supplement rather than a treatment, and any effect builds slowly over weeks rather than being felt immediately.

When to see a doctor

Joint pain that is new, worsening, one-sided, or comes with swelling, redness or fever is not something a supplement addresses, and warrants seeing a doctor rather than continuing to wait it out.

Worth knowing

• Not a complete protein source