Collagen: Do supplements work for skin and joints? Experts weigh in

Collagen is the most abundant protein in the body, forming the scaffolding that helps maintain the skin and musculoskeletal system. As people age, collagen supply declines, on average by about 1% per year after the mid-20s, with rate influenced by sun exposure, diet and stress. With a growing market of drinks, pills and topical products, the central question remains: can supplements replenish what the body loses, and if so, how effective are they?

People take collagen in various forms—from drinks and gels to pills and injections. Some enthusiasts even drink shots of the anti-ageing supplement at social events, often alongside tequila, though experts caution against mixing alcohol with attempts to support youthful skin. Kimberlie Smith, a 33-year-old mother of three who says sleep deprivation and stress in 2024 affected her appearance, began using marine collagen about six months ago. She drinks a tropical-flavoured gel daily and reports brighter, clearer skin and hair that feels thicker. “As a sleep deprived mother, it’s definitely made a difference,” she says.

Emma Wedgeworth, a consultant dermatologist based on London’s Harley Street, says there is some research suggesting oral collagen can have an impact, but she remains skeptical. The body’s digestion and absorption of collagen are not straightforward. Large collagen molecules must be broken down into smaller pieces—collagen peptides—before they might travel to the bloodstream. Even then, they would have to reach the skin to have an effect, and could instead circulate to support other organs. “There is little reliable evidence,” she notes, but there is a theory that because skin has a rapid turnover of cells, it might use these peptides more readily than other tissues.

There is also consideration of whether applying collagen directly to the skin makes a difference. “No,” Wedgworth says simply. “The collagen will just sit on the outer layer of your skin and won’t reach the dermis—the middle layer.”

There are three main types of collagen supplements: marine (from fish), bovine (from cows), and vegan. Of the three, the dermatologist recommends marine collagen for oral use because it contains more type 1 collagen—the form that helps give structure to skin, bones, tendons and connective tissues. Vegan collagen is the least effective, as these products are not collagen per se and instead provide a mix of amino acids and vitamins.

Ali Watson, a 46-year-old neuroanaesthetist and keen weightlifter, started using collagen powder a couple of years ago to protect joints. She notes the routine has extended into what she now gives to her dog, Tommy, aged by years and joints, hoping it might help his mobility. “This one is for me and, well, this one is for Tommy,” she says, pointing to two different packets in her kitchen. Watson reports her skin appears to glow, her hair seems thicker and nails are stronger. She concedes she isn’t sure whether these changes are due to the supplement, other lifestyle factors, or a bit of both. The monthly cost for both owner and dog runs around £60.

Professor Faisal Ali, a consultant dermatologist at Mid Cheshire NHS Trust, says one of the challenges for consumers and clinicians is conflicting information and interests in supplement research. A recent, small study found industry-funded research suggested collagen improved skin hydration and elasticity, while independent studies reported little or no effect. “Industry-funded studies are not inherently bad, but it’s a mixed picture,” he says. He cautions that collagen, when taken orally, does not stay in the body long enough to function as a long-term store. There is no collagen store cupboard to dip into for future needs.

Some clinics promote methods that may boost collagen production in the skin, such as laser stimulation and microneedling, which create tiny wounds to trigger repair. These can cost up to about £300 per session. For more reliable, lasting improvements, experts emphasize sun protection and overall skin health. “The best thing you can do for your skin is using decent sunblock. Sun exposure has a huge impact on aging,” Prof Ali says. A healthy diet and avoiding smoking are also important factors that can have a greater impact than collagen supplements.

Beyond the appetite for breakthroughs, the debate over collagen remains unsettled. The science shows potential mechanisms—peptides formed during digestion may interact with skin cells or other tissues—but the evidence for meaningful, consistent skin or joint benefits from oral or topical collagen remains limited. Patients should approach claims with caution, weigh costs, and consider that lifestyle measures with proven benefits can be more reliable long-term investments in health and appearance.