Collagen supplements and your skin: what the evidence shows.

01 / The trend and the protein

What happens after you swallow it.

Collagen is a structural protein, and the skin relies on it for firmness. Because skin collagen declines with age and sun exposure, the idea of “topping it up” with a drink is easy to understand. The trend is real: powders, ready-to-drink shots and gummies are sold in pharmacies, supermarkets and all over social media.

Most supplements are sold as hydrolysed collagen or collagen peptides, collagen broken into smaller pieces that are easier to absorb. Once digested, collagen is broken down into amino acids that the body sends wherever it needs protein most.[3] It does not travel to your face as collagen. The question the research tries to answer is whether these peptides still make a visible difference to skin.

Collagen in creams is a separate claim. Collagen fibres are too large to pass through the skin’s outer layers,[3] so a collagen cream works as a moisturiser, not as new collagen.

02 / The research

What the reviews actually found.

Single studies of collagen are easy to find. Systematic reviews and meta-analyses, which pool many randomised trials, give a fairer picture. Two of them point in different directions.

2021, International Journal of Dermatology

Pooled 19 trials with 1,125 participants, almost all women. It reported favourable results for hydration, elasticity and wrinkles with hydrolysed collagen compared with placebo.[2]

2025, The American Journal of Medicine

Pooled 23 trials with 1,474 participants. Across all trials collagen looked helpful, but studies not funded by industry, and high-quality studies, showed no significant effect on hydration, elasticity or wrinkles. The authors concluded there is currently no clinical evidence to support collagen supplements for preventing or treating skin ageing.[1]

Put plainly: some pooled results suggest a modest effect on how hydrated and springy skin measures in a study, but the most careful analysis to date could not separate any benefit from who funded the research.

03 / Reading the evidence

Why the results don’t line up.

• Funding. Harvard’s Nutrition Source notes that most, if not all, collagen research is funded or partly funded by related industries, which makes it hard to judge how well supplements truly work.[3] The 2025 analysis found the benefit only in industry-funded trials.[1]
• Study quality. When the 2025 review separated higher-quality from lower-quality trials, the effects did not survive in the higher-quality group.[1]
• Narrow groups. The 2021 review’s participants were almost all women,[2] so its results say little about men.

04 / Before you buy

If you are thinking of trying one.

Wanting to try collagen is understandable, and the decision is yours. A few things are worth knowing first.

1. Talk to your doctor or pharmacist.

   Especially if you are pregnant or breastfeeding, take regular medicines, or have a health condition. Supplements can interact with some medicines, and many have not been well tested in pregnancy.[4] This article does not suggest any amount or product; that belongs in a conversation with someone who knows your health.

2. Read the label realistically.

   In the United States, supplements are not reviewed for effectiveness before they are sold,[4] and Harvard’s Nutrition Source points out that it is not always clear exactly what a product contains or whether it will do what the label promises.[3] “Natural” does not automatically mean safe.[4]

3. Keep the basics in place.

   Harvard’s Nutrition Source warns that a supplement can become an excuse to skip habits that actually protect collagen.[3] If you are weighing a monthly supplement against a good sunscreen, where to spend and where to save may help.

Available research has not shown negative side effects in people given collagen supplements, though concerns have been raised about possible heavy-metal contamination in some products.[3] The same thinking applies to other inside-out beauty trends; glutathione and skin tone looks at another one.

05 / What is better supported

Protecting the collagen you already have.

The American Academy of Dermatology’s advice for reducing premature skin ageing does not include a supplement. It starts with daily sun protection, because the sun plays a major role in ageing skin early, and continues with not smoking, eating plenty of fruit and vegetables, cleansing gently, moisturising daily and stopping products that sting or burn.[5]

• Sunscreen every day. Choosing a sunscreen you will actually use is the most practical place to start.
• Food that supports collagen production. Harvard’s Nutrition Source lists protein, zinc and vitamin C sources such as fish, eggs, legumes, nuts, citrus fruit, peppers and tomatoes, while noting there is little research showing that eating collagen itself benefits skin.[3]
• A steady routine. A skincare routine does not need to be complicated, and topical ingredients such as retinoids or peptides can be discussed on their own merits.

If firmness is your main concern, for example after weight loss (see skin changes after weight loss), professional options such as Forma or CACI Quantum may come up in a consultation. Whether either suits you, and what it can realistically do, is a conversation to have in person. Sudden or unexplained skin changes, or changes alongside other symptoms, are a question for your doctor.

A few common questions

Frequently asked questions.