Collagen Supplements and Skin Health: A Review of the Evidence

A growing number of people are turning to collagen supplements in an effort to reduce wrinkles and maintain youthful skin. But do these products live up to their promises? As someone who has been studying the science of skin aging, I was eager to investigate.

Collagen is a crucial protein found throughout our bodies, forming the framework that gives skin its strength and elasticity. It's often likened to a trampoline mat - strong yet flexible. But as we age, our skin produces less collagen, leading to sagging and wrinkles. This has led many to wonder if taking collagen supplements could be the answer.

The idea behind collagen supplements is straightforward: by topping up declining levels of this essential protein, we can restore our skin's youthful appearance. However, research suggests that the relationship between oral collagen intake and skin health may not be as direct as previously thought. In fact, the body has a complex way of processing ingested collagen.

When taken orally, collagen is broken down into its constituent amino acids during digestion, rather than being absorbed intact by the body. This raises questions about how effective these supplements can really be in promoting healthy skin aging - and whether they're worth the cost.

The breakdown of collagen into smaller fragments is a key aspect of how our bodies process these supplements. When we ingest hydrolysed collagen, which contains individual chains of 40 or fewer amino acids, it's quickly broken down in our digestive systems into even smaller fragments consisting of just one to three amino acids.

This fragmentation occurs not only with collagen supplements but also when we consume whole collagen in foods such as salmon skin and bone broth that contain gelatine. These tiny amino acid fragments are then added to the pool of amino acids derived from other protein-rich foods like meat, dairy, and legumes.

The skin uses these amino acid building blocks to synthesize new collagen, but the efficiency of this process declines with age. This is according to James Varani, a pathologist at the University of Michigan who has extensively studied skin collagen. He notes that there's no difference between taking a collagen supplement and consuming a nutrient-rich food like a good steak.

Varani's research suggests that the reason our skin loses collagen as we age isn't due to a lack of necessary ingredients but rather an inefficiency in the cellular machinery responsible for assembling these components into new collagen.

The idea that taking collagen supplements can smooth away wrinkles is a notion that's been gaining traction in recent years. However, a closer look at the available research reveals that these claims might be overstated.

Studies claiming to show significant reductions in wrinkle depth after taking collagen supplements often report tiny differences - mere fractions of a millimetre. These results may not translate into noticeable improvements in skin appearance.

Dermatologist Anjali Mahto and biostatistician David Grimes have sounded the alarm on methodological concerns in existing studies. They point out that many of these studies are industry-funded or involve authors with commercial ties to collagen manufacturers, raising questions about selective reporting and bias.

Their criticism is not without merit, given that an overwhelming proportion of research in this area has been funded by companies with a vested interest in the outcome. This can lead to overly optimistic conclusions being drawn from flawed data.

Exercise, on the other hand, has been shown to have a more tangible impact on collagen production. Regular physical activity has been found to increase the expression of collagen genes, suggesting that incorporating exercise into one's routine may be a more effective way to support skin health than relying on supplements alone.

Sun protection is crucial for maintaining healthy skin, as excessive exposure to ultraviolet radiation from the sun can lead to the breakdown of collagen. Dermatologists emphasize the importance of shielding the skin from harmful UV rays, which stimulate enzymes that degrade collagen.

Tretinoin, a vitamin A derivative, has been shown to increase collagen levels since the 1990s. This prescription-strength treatment is often recommended by dermatologists for its ability to reduce wrinkles and improve skin texture. However, it can cause side effects such as dryness, redness, and peeling if not used carefully.

Certain therapies that intentionally injure the skin in a controlled manner can also stimulate collagen production. These include laser treatments, microneedling, dermabrasion, and deep chemical peels. While these methods are effective at boosting collagen levels, they come with significant drawbacks, including redness, rawness, and blistering.

A gene therapy originally developed for a rare genetic condition has shown promise in promoting collagen production. This treatment targets individuals with recessive dystrophic epidermolysis bullosa, a disorder characterized by extremely fragile skin and large, painful wounds.

A new gene therapy has been approved for individuals with a rare genetic disorder that causes extremely fragile skin.

This treatment introduces new collagen genes into the skin to boost collagen production and help repair damaged tissue. The US was the first country to approve this therapy in 2023, followed by the UK later this year.

Researchers are now exploring whether a modified version of this gene therapy can reverse signs of aging in people with normal skin.