Collagen supplements: The surprising science behind this popular celebrity wellness fad

In the 1990s, everyone who watched Friends wanted Jennifer Aniston’s haircut. Now, she’s hoping that we’ll all want to copy her morning cuppa: a coffee with a spoonful of her collagen supplement stirred in. But is there any scientific support for the claim that the supplement will “promote a youthful appearance”?

Collagen is one of the most abundant proteins in the body. It plays a role in building cells for skin, hair and nails, and as connective tissue in cartilage, muscle, and tendons. Studies have shown collagen’s effectiveness in reducing symptoms of arthritis, repairing tendons and ligaments, and as a scaffold for growing tissues for testing in the laboratory.

The production of collagen is ramped up during childhood and puberty, but as we reach our late-20s, our ability to replenish collagen starts to decline. The main cells that synthesise collagen for the skin are called fibroblasts and they’re sensitive to damage from sunlight and air pollution. The decline of collagen has been suggested as a main cause of wrinkles, with one study finding an 80-year-old’s collagen production is decreased by 75 per cent compared with a young adult’s.

So can collagen supplements stave off wrinkles, sagging skin and brown spots, as their sellers claim? Technically, collagen supplements – whether they’re taken as pills, mixed up from a powder, or drunk as a hydrogel shot – contain a slightly different form of collagen to that made in our bodies. This is because pure collagen would be hard for us to digest. To put collagen into a supplement, it is therefore partially broken down in a process called hydrolysis. The result, hydrolysed collagen, can be consumed and digested safely.

But does it work? A review of 19 available studies, with a combined total of more than 1,000 participants, found that hydrolysed collagen supplements were effective in reducing the appearance of skin ageing if taken for at least 90 days.

However, the same review cautioned that the individual studies could’ve been limited by their small numbers of participants. They also pointed out that these studies are often funded, at least in part, by the companies that manufacture the supplements. The authors conclude that claims by sellers, and their supporters, “surpass any evidence currently proven in the literature.”

While some have said that the temperature of your beverage could diminish the benefits of collagen supplements, the limited amount of research available suggests you’d need much higher temperatures than that of your morning mocha – 150°C at least – to begin breaking down collagen into something unusable by your body.

Still, as celebrity wellness fads go, collagen supplements seem to be slightly more scientific than things like perineum sunning and coffee enemas. But having the skincare of the stars doesn’t come cheap; the collagen supplement Anniston promotes costs just under £40 a tub, working out at £1.41 for each daily dose.

Read more:

• Why is human skin so fragile?
• Why do people get wrinkles?
• How do you get healthy hair?
• Does sunshine make us happier and healthier?

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