While I was writing my forthcoming book on the science of the skin, the number one thing that friends asked me to look into was collagen supplements. Do they really reduce wrinkles as promised? As a 40-year-old with increasingly crinkly skin, I wanted to know the answer to this, too, so I spent a long time poring over the evidence and interviewing skin scientists and doctors.
Collagen is the major structural protein in our skin, forming a woven network of fibres that is strong but flexible, a bit like a trampoline mat. As we age, our skin produces less collagen to maintain this structure, leading to sagging and wrinkling.
The logical solution to declining collagen levels is to top them back up, which is the basis for taking collagen supplements. However, I discovered that it isn鈥檛 that simple, because taking in collagen through your mouth doesn鈥檛 magically transport it to your skin.
Advertisement
Collagen for supplements is usually sourced from the skin of cattle, pigs or fish left over from meat and seafood processing. It is treated with chemicals to chop the collagen proteins into smaller bits that are easier to process into pills and powders. Whole collagen is made of three protein chains of more than 1000 amino acids each, arranged as a triple helix, whereas processed collagen that is used in supplements, called hydrolysed collagen, contains single chains of 40 or fewer amino acids.
When we ingest hydrolysed collagen, our digestive systems break it into even smaller fragments of just one to three amino acids. The same thing occurs when we eat whole collagen in foods like salmon skin, or sip bone broth, which contains gelatine, a heat-degraded form of collagen.
These tiny fragments add to a pool of amino acids that we get from other proteins in foods like meat, dairy and legumes. The skin uses these amino acids as building blocks to make new collagen. James Varani, a pathologist at the University of Michigan who has been studying skin collagen for decades, told me there鈥檚 no difference between taking a collagen supplement and eating 鈥渁 good steak鈥�, because they both provide the amino acids needed for making new collagen.
Notably, Varani and his colleagues found that the reason our skin loses collagen with age isn鈥檛 because it lacks the ingredients for making it. Instead, its cellular machinery for assembling these ingredients into collagen . That means that taking collagen supplements to fix wrinkles is like buying more sugar to fix a broken assembly line at a chocolate factory.
Plenty of studies claim to show that collagen supplements smooth away wrinkles, but they need to be taken with a grain of salt. Some, for example, report significant in participants taking collagen supplements compared with those taking a placebo, but if you look at their actual numbers, the difference is a fraction of a millimetre. This is unlikely to make a meaningful difference to skin appearance, and you have to wonder about the accuracy of measurements on such a tiny scale anyway.
In September, dermatologist Anjali Mahto at clinic Self London and biostatistician David Grimes at Trinity College Dublin published a paper highlighting that 鈥渢emper [their] optimistic conclusions鈥�. They also noted that 鈥渁n overwhelming proportion of studies are industry-funded or involve authors with commercial ties to collagen manufacturers, raising concerns about selective reporting and bias鈥�.
It鈥檚 disappointing that collagen supplements don鈥檛 live up to the hype, but there are some other collagen-optimising strategies with better evidence to support them, including , which has been found to increase the expression of collagen genes. Every dermatologist I have ever interviewed has also stressed the importance of sun protection, because it is well established that ultraviolet radiation from the sun stimulates the release of enzymes in the skin that .
Several dermatologists have told me that the best thing to rub on the skin to reduce wrinkles is tretinoin, a vitamin A derivative that has been known to since the 1990s. It requires a prescription because it can cause dryness, redness and peeling if not used carefully.
Therapies that injure the skin in a safe, controlled way also by activating natural healing mechanisms. These include laser therapies, microneedling, dermabrasion and deep chemical peels. Unfortunately, they are expensive and often make the skin red, raw and blistered, requiring a period of hiding from public view.
One of the most promising treatments I have come across in my research is a gene therapy that was originally developed for people with low collagen levels due to a rare genetic condition called recessive dystrophic epidermolysis bullosa. Sometimes referred to as the 鈥渨orst disease you鈥檝e never heard of鈥�, it is characterised by extremely fragile skin and large, painful wounds.
The , which introduces new collagen genes into the skin to enhance collagen production, was approved in the US in 2023 and in the UK this year for people with this condition. Now, a modified version is being evaluated in clinical trials involving people with aged skin to see if it has rejuvenating effects.
Our desire for younger-looking skin is largely driven by vanity, but as I also explore in my book, there is growing evidence that the health of our skin directly affects the health of our inner organs, which is another reason to look after it. I鈥檝e decided not to waste my money on collagen supplements, but I have invested in a very dorky wide-brim hat, to at least try to protect the collagen I still have.
Alice Klein is the author of (out in January 2027)
