This article is the scientific rationale for why I take supplemental collagen in my diet. But first I want to ask a couple of opening questions:
What is a healthy diet?
I don’t have the answer to this question. Based on the food pyramid that we all grew up with, I don’t think the scientific community has the answer either. The available data shows a growing epidemic of obesity and illness in Western countries (Figure 1). It’s perhaps not surprising then that Big Pharma’s best-selling drug in 2024 will be related to weight loss and diabetes.
So, let me ask another question:
What do we want our diets to do?
I think we are looking for our diets to facilitate what we want from our bodies, which encompasses a range of answers. This means being high functioning at work, strong and durable in physical activities, e.g., sports, strength training, hiking, etc, and maintaining an attractive and youthful physical appearance. To distill this - we want our diets to allow us to enjoy the maximum potential of our bodies.
Okay, this is becoming less nebulous. Physical performance and physical attributes are certainly things we can baseline and measure. If it’s something we can measure, we can apply the scientific method to test ways we can improve it. This is why I’m interested in health supplements.
There are a ton of health supplements. It’s a highly unregulated area and many of them are garbage. So I’m going to start with one that I have a high degree of confidence in, that is collagen. Collagen supplementation has a significant body of literature behind it. Not just individual studies, but meta-analyses that conclude a given benefit by studying a collection of studies. What are the overall conclusion? Supplemental collagen appears to be helpful for improving skin health, body composition, bone health, and joint health. We will review the data for these in this article along with what these studies recommend for dosing to achieve the reported effects.
What is collagen?
Collagen is the primary structural protein in the human body accounting for anywhere between 25-35% of total protein content. It is found in most tissues to to some degree - it is the key element of connective tissues, skin, bones, tendons, and ligaments. On a molecular level, collagen consists of long chains of amino acids braided in a triple helix structure, giving it great mechanical properties and flexibility (Figure 2). In simple terms, collagen is the main protein that holds your body together, providing strength and structure.
Collagen is produced by a few different cells in the body, primarily fibroblasts, by combining amino acids from protein-rich foods. This is also facilitated by nutrients like vitamin C, zinc, and copper. However, as we age, the body produces less and lower-quality collagen (Figure 3). This leads to common signs of aging like wrinkles, sagging skin, and weaker cartilage. This reduction in collagen only gets worse with aging, starting typically in the mid 20s and accelerating as we get older. Some common symptoms:
Wrinkles and Fine Lines: Due to decreased skin elasticity.
Joint Pain and Stiffness: Resulting from worn-down cartilage.
Weakened Muscles: Due to reduced muscle mass and strength.
Bone Density Loss: Making bones more fragile and prone to fractures.
This importance in maintaining healthy skin, bones, muscle, and body composition has made collagen a popular dietary supplement. But a critical question may be what does the literature support for collagen supplementation?
Research supported benefits of collagen supplementation:
How do we know that collagen actually helps as a supplement? Well, let’s look at the literature. But not just single publications, collagen is so well studied for its various claims that there are meta-analyses of the research, which means that there are studies synthesizing the information from many studies.
Skin health
Collagen supplementation is commonly discussed for its benefits to skin health. A meta-analysis published in the International Journal of Dermatology reviews the effects of collagen peptide supplementation on skin health. It synthesizes findings from 19 studies with over 1,100 participants between 20 and 70 years old. The meta-analysis found that hydrolyzed collagen supplementation significantly improved skin hydration, elasticity, thickness, and reduced wrinkles compared to placebo for all groups. The benefits were observed after 90 days of supplementation and were maintained for 30 days post-intervention. The review highlighted that collagen peptides increase the bioactivity of dermal fibroblasts, enhancing collagen synthesis, and thus improving the clinical signs of skin aging (de Miranda et al, 2021).
Body composition and fat mass
Collagen peptide supplementation has been shown to have a positive impact on body composition, specifically by reducing fat mass and increasing fat-free mass. A systematic review and meta-analysis published in the British Journal of Nutrition examined the effects of collagen peptide supplementation on various cardiovascular and metabolic markers. The analysis included 12 randomized, placebo-controlled trials with a total of 748 participants. The results indicated that collagen peptide supplementation significantly decreased fat mass by 1.21 kg and increased fat-free mass by 1.49% based on body mass percentage. These effects were more pronounced in individuals aged 50 years and older, men, and those who were overweight or obese, as well as participants who combined supplementation with exercise (Jalili et al, 2022).
Joint health
A meta-analysis published in International Orthopaedics evaluated the effectiveness of collagen supplementation in reducing osteoarthritis (OA) symptoms. This analysis included 12 randomized, placebo-controlled trials involving 1,123 participants. The results demonstrated that collagen supplementation significantly reduced OA symptoms, as measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Visual Analog Scale (VAS) scores. Specifically, collagen treatment led to a significant reduction in total WOMAC score (WMD -8.00; 95% CI -13.04, -2.95; p = 0.002) and VAS score (WMD -16.57; 95% CI -26.24, -6.89; p < 0.001). These findings indicate that collagen is effective in improving joint health and reducing pain and stiffness in individuals with osteoarthritis (Garcia-Coronado et al, 2019).
Bone health
While I did not find any meta-analysis for bone health, there are several studies implying collagen supplementation improves bone health. A study published in the Journal of Musculoskeletal and Neuronal Interactions investigated the effects of collagen peptides on bone turnover in postmenopausal women with osteopenia. This randomized prospective study involved 51 postmenopausal women who were divided into two groups: one group received 5 grams of collagen peptides daily along with calcium and vitamin D, while the control group received only calcium and vitamin D. After three months, the collagen peptide group showed a significant decrease in markers of bone resorption and an increase in markers of bone formation, indicating improved bone metabolism compared to the control group (Argyrou et al, 2020).
Additionally, a study published in the International Journal of Sport Nutrition and Exercise Metabolism evaluated the impact of collagen supplementation combined with a jumping exercise program on bone mineral density (BMD) in elite road-race cyclists. This 18-week open-label, randomized trial found that participants who took 15 grams of collagen daily and performed jumping exercises five times a week experienced significant improvements in BMD and bone strength compared to those who did not receive collagen supplementation (Hilkens et al, 2023).
Why does supplementing collagen work?
This is a question I’ve wondered myself. Surely the collagen peptides we are consuming as supplements are already broken down significantly and are even further degraded as we consume them. So how does this translate to the improvements observed in the meta-analyses?
Collagen has a constant turnover throughout the body. It is both generated and degraded. In the skin and muscle, collagen is mainly produced by cells called fibroblasts. Similarly, collagen is produced in bone (by osteoblasts) and in cartilage (by chondrocytes). Within these tissues, there are mechanisms by which collagen is degraded, this typically happens through the release of enzymes within these tissues that degrade the collagen.
With that background, we can see a bit of how the collagen supplement works on these mechanisms.
Stimulation of new collagen production: These peptides stimulate collagen-producing cells to synthesize more collagen - at the same time, they serve as the amino acid building block material for new collagen.
Reducing collagen degradation: the collagen peptide metabolites are believed to inhibit the enzymes responsible for degrading collagen. These enzymes are sensitive to the degradation products of collagen, which act as a signal, or negative feedback loop, to slow degradation.
Are there some reasons we should be skeptical about collagen supplementation?
While there are promising findings regarding the benefits of collagen supplementation, there are several reasons to be skeptical.
Variability in supplement quality. The formulation of collagen can range significantly between products, even depending upon the source of collagen (e.g., bovine, marine, porcine), manufacturing process, or additional ingredients. Furtheremore, there is little regulation in supplements. As a result the product may not contain exactly what it claims, worse, it could be contaminated.
Absorptions and bioavailability. When we consume collagen peptides, they are broken down into smaller peptides and amino acids. There is debate over how much of this product actually reaches the target tissues.
Dietary sources vs supplements. Collagen and its precursors can be obtained from dietary sources such as bone broth, meat, and fish. There is ongoing debate about whether supplements offer significant advantages over these whole food sources.
General considerations, e.g., safety, dosage, etc.
Collagen supplements are generally considered extremely safe supplements. Particularly in comparison to any drugs that could positively influence all the traits collagen supplements have been shown to impact.
Okay, I’m convinced it’s a great supplement, but which should I take and how much?
The dosage of collagen in the studies reviewed above varied from 2.5 grams to 15 grams per day. This probably depends on the specific application and the bioavailability of a given form. If you want to be on the safe side, why not just use the high end of this dosing at stick with 15 grams per day? Particularly since collagen seems to be well tolerated.
Conclusion:
This is not just an article about collagen supplements, but why I take them based on the body of literature. The data indicates that collagen supplementation offers promising benefits for improving skin elasticity, reducing wrinkles, enhancing hydration, improving body composition, supporting joint health, and boosting bone density. There are clear caveats, particularly regarding supplement quality in this lightly regulated space. That being said, I think the juice here is worth the squeeze.
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References:
Argyrou, C., Karlafti, E., Lampropoulou-Adamidou, K., Tournis, S., Makris, K., Trovas, G., Dontas, I. and Triantafyllopoulos, I.K., 2020. Effect of calcium and vitamin D supplementation with and without collagen peptides on bone turnover in postmenopausal women with osteopenia. Journal of musculoskeletal & neuronal interactions, 20(1), p.12.
García-Coronado, J.M., Martínez-Olvera, L., Elizondo-Omaña, R.E., Acosta-Olivo, C.A., Vilchez-Cavazos, F., Simental-Mendía, L.E. and Simental-Mendía, M., 2019. Effect of collagen supplementation on osteoarthritis symptoms: a meta-analysis of randomized placebo-controlled trials. International orthopaedics, 43, pp.531-538.
Hilkens, L., van Schijndel, N., Weijer, V.C., Decroix, L., Bons, J., van Loon, L.J. and van Dijk, J.W., 2023. Jumping exercise combined with collagen supplementation preserves bone mineral density in elite cyclists. International journal of sport nutrition and exercise metabolism, 1(aop), pp.1-10.
Jalili, Z., Jalili, F., Moradi, S., Bagheri, R., Moosavian, S.P., Naeini, F., Mohammadi, H., Ghoreishy, S.M., Wong, A., Travica, N. and Kermani, M.A.H., 2023. Effects of collagen peptide supplementation on cardiovascular markers: a systematic review and meta-analysis of randomised, placebo-controlled trials. British Journal of Nutrition, 129(5), pp.779-794.
Khatri, M., Naughton, R.J., Clifford, T., Harper, L.D. and Corr, L., 2021. The effects of collagen peptide supplementation on body composition, collagen synthesis, and recovery from joint injury and exercise: a systematic review. Amino acids, 53(10), pp.1493-1506.
de Miranda, R.B., Weimer, P. and Rossi, R.C., 2021. Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta‐analysis. International journal of dermatology, 60(12), pp.1449-1461.
Purnell, J.Q., 2023. Definitions, classification, and epidemiology of obesity.
Reilly, D.M. and Lozano, J., 2021. Skin collagen through the lifestages: Importance for skin health and beauty. undefined, 8, pp.N-A.
Varani, J., Dame, M.K., Rittie, L., Fligiel, S.E., Kang, S., Fisher, G.J. and Voorhees, J.J., 2006. Decreased collagen production in chronologically aged skin: roles of age-dependent alteration in fibroblast function and defective mechanical stimulation. The American journal of pathology, 168(6), pp.1861-1868.
What brand do you recommend?
Could we tailor collagen supplementation more precisely to individual needs and optimize its effectiveness, or do you think we're still a long way from such personalized approaches in supplementation?