Collagen: More than just skin deep
Written by Ella Robb, BSc (Hons) Human Nutrition student at Ulster University, currently on clinical placement at ARK Health Group, with a passion for evidence-based nutrition and gut health.
Collagen has become one of the most talked about ingredients in the health and beauty space. From skin elasticity to joint support, it is often described as a foundational protein for healthy ageing.
But beyond the marketing and influencer hype, what does the science actually say?
As part of our Inside the Formulation series, we are breaking down the ingredients we use and exploring the research behind them. This week, we are focusing on collagen, what it does, how it works, and whether clinical evidence supports its use.
What Is Collagen and Why Does It Matter?
Collagen is the most abundant structural protein in the human body. It acts as a scaffold, providing strength, elasticity and integrity to tissues including:
Skin
Cartilage and joints
Tendons and ligaments
Bone
Blood vessels
Over 90 percent of the body’s collagen is Type I collagen, found primarily in skin, bone and connective tissue. Type II collagen is dominant in cartilage, while Type III supports skin and vascular tissues (de Miranda et al., 2021).
Collagen is rich in glycine, proline and hydroxyproline. Its synthesis also requires vitamin C as an essential enzymatic cofactor (DePhillipo et al., 2018). Without adequate vitamin C, collagen production cannot occur efficiently.
Collagen and The Decline With Age
From our mid 20s onward, collagen production begins to quietly decline, long before most of us notice visible changes.
This decline accelerates due to UV exposure, smoking, poor sleep, chronic stress and hormonal changes, particularly during menopause.
Reduced collagen contributes to wrinkles, decreased elasticity, joint stiffness and slower tissue recovery.
Supporting collagen production through nutrition, lifestyle and targeted supplementation has therefore become a key focus in healthy ageing.
How are Collagen Supplements Absorbed?
One common question is whether collagen is simply broken down like any other protein. Most supplements contain hydrolysed collagen peptides, which are pre broken into smaller fragments to improve absorption.
After ingestion, collagen is digested into amino acids and small peptides. Research shows that collagen derived di and tri peptides can be detected in human plasma after oral consumption and may stimulate fibroblast activity involved in connective tissue synthesis (Martínez-Puig et al., 2023).
Hydrolysed collagen is therefore considered bioavailable. It is important to note that collagen is not a complete protein, as it lacks the essential amino acid tryptophan. It should complement, not replace, a balanced protein rich diet (Pu et al., 2023).
Collagen and Skin Health
Does Collagen Improve Skin Elasticity and Hydration?
Skin ageing is associated with collagen fragmentation and reduced dermal density. Several high quality systematic reviews have examined whether oral collagen supplementation can improve measurable skin parameters.
A 2023 systematic review and meta analysis of 26 randomised controlled trials found that hydrolysed collagen supplementation significantly improved skin hydration, elasticity and wrinkle depth compared with placebo (Pu et al., 2023).
Similarly, a 2021 meta analysis concluded that daily hydrolysed collagen supplementation for 90 days reduced signs of skin ageing and improved elasticity and hydration (de Miranda et al., 2021).
Most trials used doses between 2.5 and 10 grams per day, with improvements typically observed after 8 to 12 weeks.
What This Means Practically:
Clinical evidence supports that consistent collagen supplementation can:
Improve measurable skin hydration
Enhance elasticity
Reduce wrinkle depth over time
Results are gradual rather than immediate, reflecting the natural turnover cycle of collagen in skin.
For optimal collagen synthesis, supplementation should be combined with adequate vitamin C intake (DePhillipo et al., 2018).
Collagen and Joint Health
Cartilage consists primarily of Type II collagen and proteoglycans. Degeneration of this matrix contributes to joint discomfort and reduced mobility.
Evidence in Osteoarthritis and Active Adults
A narrative review of clinical studies concluded that collagen supplementation improves joint pain and physical function in individuals with osteoarthritis and activity related joint discomfort (Martínez-Puig et al., 2023).
A randomised controlled trial in physically active adults demonstrated that 5 grams per day of specific collagen peptides for 12 weeks significantly reduced activity related knee pain compared to placebo (Zdzieblik et al., 2021).
Meta analytic data also show statistically significant reductions in pain and improvements in joint function in individuals with knee osteoarthritis (Pu et al., 2023).
Practical implications:
Collagen peptides may:
Support cartilage matrix integrity
Reduce exercise related joint discomfort
Improve functional mobility
Doses of 5 to 10 grams per day for at least 12 weeks are most commonly studied.
What about Gut Health?
Collagen’s role in gut barrier integrity is an area of growing interest.
Collagen provides glycine and proline, amino acids involved in tissue repair and cellular integrity. While mechanistic evidence is promising, human clinical trials directly assessing collagen supplementation and gut permeability remain limited.
At present, collagen’s strongest evidence base supports skin and joint health. However, given ARK Health Group’s focus on connective tissue and gut health, collagen’s structural role remains an important formulation consideration.
Who May Benefit from Collagen Supplementation?
Collagen supplementation may be particularly relevant for:
Adults aged 25 and over
Women in perimenopause or menopause
Athletes and active individuals
Individuals experiencing joint stiffness
Those focused on healthy ageing
Collagen should complement a balanced, protein rich diet and healthy lifestyle habits.
Choosing a Quality Collagen Supplement
When selecting a collagen product, consider:
Hydrolysed collagen peptides for bioavailability
Clinically studied dosing between 2.5 and 10 grams daily
Transparent sourcing
Third party quality testing
At ARK Health Group, we formulate using high quality hydrolysed collagen peptides designed to align with current clinical research on skin and joint health.
Collagen is more than a trend. It is the body’s foundational structural protein.
Peer reviewed research supports that hydrolysed collagen peptides can improve skin hydration and elasticity, reduce wrinkle depth and support joint comfort when taken consistently in clinically studied doses.
While not a replacement for overall nutrition, collagen supplementation represents a science supported strategy for supporting connective tissue health and healthy ageing.
As part of our Inside the Formulation series, our aim is to move beyond trends and provide evidence based clarity around the ingredients we use.
References:
DePhillipo, N. N., Aman, Z. S., Kennedy, M. I., Begley, J. P., Moatshe, G., LaPrade, R. F., & LaPrade, C. M. (2018). Efficacy of vitamin C supplementation on collagen synthesis and oxidative stress after musculoskeletal injuries: A systematic review. Orthopaedic Journal of Sports Medicine, 6(10), 2325967118804544. https://doi.org/10.1177/2325967118804544
de Miranda, R. B., Weimer, P., & Rossi, R. C. (2021). Effects of hydrolyzed collagen supplementation on skin aging: A systematic review and meta-analysis. International Journal of Dermatology, 60(12), 1449–1461. https://doi.org/10.1111/ijd.15518
Martínez-Puig, D., Juárez-Castelló, C. A., & de la Puerta, R. (2023). Collagen supplementation for joint health: A narrative review of clinical studies. Nutrients, 15(5), 1176. https://doi.org/10.3390/nu15051176
Pu, S. Y., et al. (2023). Effects of oral collagen for skin anti-aging: A systematic review and meta-analysis. Nutrients, 15(9), 2080. https://doi.org/10.3390/nu15092080
Zdzieblik, D., Oesser, S., Baumstark, M. W., Gollhofer, A., & König, D. (2021). Specific collagen peptides improve knee joint discomfort in young physically active adults: A randomized controlled trial. Nutrients, 13(3), 792. https://doi.org/10.3390/nu13030792
Clark, K. L., Sebastianelli, W., Flechsenhar, K. R., Aukermann, D. F., Meza, F., Millard, R. L., Deitch, J. R., Sherbondy, P. S., & Albert, A. (2008). 24-Week study on the use of collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain. Current Medical Research and Opinion, 24(5), 1485–1496. https://doi.org/10.1185/030079908X291967
