Collagen is the most abundant protein in the body: the scaffolding of skin, joints, tendons and bone. From our mid-twenties we produce roughly one per cent less of it each year, which is the polite biological explanation for most of what we call ageing. The supplement industry noticed.
Collagen powders, capsules and drinks are now a multi-billion pound category, promising plumper skin, stronger nails and happier joints. The question is whether swallowing collagen turns into skin collagen, and the honest answer is: partly, maybe, with caveats.
The case for
When you ingest hydrolysed collagen, it is broken into peptides and amino acids. Some of these peptides survive digestion and appear in the bloodstream, and there is laboratory evidence that they may signal skin cells to produce more collagen of their own. A number of randomised trials have reported modest improvements in skin elasticity and hydration after eight to twelve weeks of daily supplementation.
The case for scepticism
Many of those trials are small, short, and funded by the companies selling the product. The improvements, where found, are measurable but subtle, the kind an instrument detects and a mirror may not. Your body also does not take requests: the amino acids from collagen may be used anywhere protein is needed, not routed helpfully to your face.
It is also worth saying that collagen is an incomplete protein, and eating enough total protein, alongside vitamin C, which is genuinely required for collagen synthesis, achieves much of the same input for less money.
If you enjoy your daily scoop and can afford it, there is no strong reason to stop. Just be suspicious of anyone claiming it will turn back a decade. Nothing in a tub does that.
