The benefits of collagen for skin and anti-ageing are vastly popular thanks to its frequent mention in cosmetic advertisements, but what else is collagen useful for?
Collagen is one of the most prevalent proteins found within mammals, and is the most abundant protein in the human body. It is responsible for several biological functions, one of which is to provide structural support in connective tissue, muscle and skin.
It is the major component of connective tissues that make up several body parts, including: tendons, ligaments, skin, and muscles.
In addition to the benefits of collagen, in this article we will be exploring the following topics:
- What is Collagen?
- What is the Function of Collagen in the Body?
- What Are The Benefits of Collagen?
- Collagen Side Effects
- Collagen Dosage
- When to Take Collagen?
- Food Sources of Collagen
- Collagen Nutritional Value
- Other FAQs
Supplementing with collagen may have a variety of health benefits, from relieving joint pain to improving skin health, but before we get into that, check out our REPs & CIMSPA accredited personal trainer courses if you’re interested in a rewarding career in the fitness industry.
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What is Collagen?
Collagen is the most common protein found within the human body, accounting for approximately one third of its overall protein composition.
Often described as scaffolding for the skin, collagen is one of the primary building blocks of our muscles, skin, bones, ligaments, connective tissues and tendons. It is also present in many other parts of the body, such as the teeth, blood vessels and corneas (the clear, protective outer layer of the eye).
A long and fibrous structural protein that is rope-like in appearance, the human body contains at least 28 different types of collagen. However, type 1 is the most prevalent; with type 2 and 3 behind it - as a collective they make up for 80-90% of collagen in the body.
To put it simply, collagen is essential for building muscle and the reparation of cells. These are obvious vital functions of the human body needed to stay healthy. As mentioned, it provides much of the structure and elasticity in the mentioned body parts.
As we age, our bodies experience a natural decline in collagen levels. This is what leads to a number of recognisable signs of aging, such as: joint pain, wrinkles, ‘saggy’ skin, weak muscles, and stiffer tendons and ligaments.
Many definitions of collagen refer to it as the glue that holds much of the body together, which is further reflected in the name, as the word “collagen” actually roots from the Greek word “kólla,” meaning glue.
What is the Function of Collagen in the Body?
Collagen appears in different forms which are dependent on the degree of mineralisation it has undergone. The varying degrees of mineralisation mean that you can find collagen in various parts of the body, such as the cornea, skin, tendon, cartilage and bone.
As we mentioned earlier, there are at least 28 different types of collagen. The human body, along with available supplements, is predominantly made up of types 1, 2 and 3, but what is the difference?
Type 1 collagen assembles into extremely tensile fibrils (a small filament or fiber: such as a root hair) and serves a leading structural role in the body’s tissues. This is likely the form of collagen you are thinking of when referring to the health of the skin, hair and nails.
It is the most prevalent type of collagen found in connective tissues including skin, tendon and bone. Type 1 collagen is the major protein component of the bone extracellular matrix (this can be defined as the protein ‘scaffolding’ for all cells to build upon in the process of bone regeneration).
Type 2 collagen also forms fibrils. It is the major collagen in cartilage and has smaller, randomly orientated fibrils which impact strength, flexibility and compressibility. This form allows joints to absorb shocks, be flexible and provide support to localised bone joints.
Type 3 collagen works alongside and contributes to type 1 collagen to form strong, elastic fibrils. It is found mainly in reticular fibres, which are fine fibrous connective tissues that occur in networks to make up the supporting tissue of organs.
What Are The Benefits of Collagen?
We have briefly outlined a couple of the benefits of collagen supplements, however below we will take an in depth look into seven of the most commonly researched points that hold sufficient scientific evidence.
It is worth noting that there are thought to be more benefits of collagen beyond this, however as it stands there is not enough data to confirm their effectiveness.
#1 Improves Skin Health
Let’s begin with one of the most recognised and praised benefits of collagen for women and men.
The collagen benefits for skin are definitely the most researched, and are where it gains much of its popularity from. Collagen is a predominant component of the skin as it plays a primary role in strengthening it, as well as benefiting its elasticity and hydration.
It is what prevents our skin from sagging and promotes that plump look associated with youth. However, from our mid-20s our collagen levels naturally begin to decline and with this, signs of aging slowly begin to develop over time.
While this is a completely natural occurrence, a number of studies have found that collagen peptides (small proteins from animal products) and supplements containing collagen can slow the signs of ageing in your skin by promoting a youthful appearance and reducing wrinkles and dryness.
There is ample science-based evidence to support this theory, for instance in a 2019 review published in the Journal of Drugs in Dermatology, researchers analysed 11 existing studies that used a sample of more than 800 patients who supplementented with up to 10g of collagen a day, with the goal of improving skin health.
The findings confirmed that the collagen supplement improves skin elasticity, as well as helps it hold onto moisture better and rev the density of collagen fibers within skin.
For an alternative way to boost your collagen levels, a single cup of blueberries contains 24% of your daily recommended intake of Vitamin C, which equates to a big increase in collagen production - this is just one of the many the benefits of blueberries that you can read about in our guide.
Again, another study conducted in 2015 found that post-menopausal women who took one collagen-mixed beverage every day for a period of 12 weeks experienced significant reduction to the depth of facial wrinkles, along with increased skin elasticity and hydration - further demonstrating that collagen benefits for skin are vast, effective and undeniable.
The wrinkle-reducing and anti-ageing benefits of collagen supplements have been ascribed to their ability to stimulate the body to produce collagen on its own. It is also suggested that such supplements could promote the production of other proteins, such as fibrillin and elastin, which both help to structure the skin.
Additionally, there are claims that collagen could help to prevent skin conditions such as acne, however there is no sufficient scientific evidence to support this claim to date. Nevertheless, the collagen benefits for skin are in no way limited.
#2 Increases Muscle Mass
In addition to the collagen benefits for skin, the collagen benefits for bodybuilding and gym enthusiasts have become a popular talking point in the weightlifting community. This is due to their rumoured ability to enhance muscle mass, but is this accurate?
Similarly to how it affects skin health, the natural decline in collagen that occurs with age causes a natural decline in muscle mass. Between 1–10% of the body’s muscle tissue is made up of collagen and as we lose this, it makes sense that muscle mass will suffer consequently, as collagen is necessary to keep the muscles strong and functioning properly.
Collagen peptides are characterized by their high levels of specific amino acids glycine, hydroxyproline, proline, and alanine; glycine specifically is an important buidling block for creatine.
You can learn more in-depth about amino acids and their benefits here.
Creatine is an organic compound that is known to build strength and improve muscle mass and athletic performance, therefore by increasing the levels of creatine through collagen supplementation, it is suggested to be another way in which collagen could increase muscle mass.
There is conclusive evidence to show that supplementing with collagen can promote the synthesis of certain muscle proteins such as creatine, as well as stimulating muscle growth after exercise.
Additionally, collagen can also reverse ageing trends, not only in healthy adults but in those who are diagnosed with sarcopenia (an age related condition defined by the involuntary loss of skeletal muscle mass and strength).
For instance, in a 2015 study that saw 27 elderly men with sarcopenia take 15g of collagen a day while participating in an exercise program for 12 weeks, the findings showed that when compared with men who exercised but did not take the collagen supplementation, those who did gained a significant amount more muscle mass and strength.
While the study looked explicitly at elderly participants, it was implied that the increased muscle mass benefits of taking collagen would apply to anyone.
While the research is sparse and more is certainly needed in order to confirm the true extent of how collagen benefits muscle mass, the existing research to date offers promising results.
#3 Great Source of Easily Digestible Protein
As we know, collagen is the most abundant protein in the human body, responsible for a number of useful functions; with collagen benefits ranging from our physical to medical health.
Of all the food groups, the human body has to work particularly hard to digest protein from food sources such as beef and chicken. The digestion of protein is the most time consuming, roughly taking over three hours to break down and assimilate proteins.
The reason for this is that protein molecules are long chains with strong links, and in order to break down their resistance, the combination of chewing as well as the simultaneous attack of various gastric, pancreatic, and biliary juices is needed.
Due to this process, many people find that they experience negative digestive symptoms after a meal, such as burping or stomach pain.
However, collagen supplements offer a hydrolysed form of protein, meaning that the collagen is significantly broken down, making it much easier for your body to digest. This avoids many of the side effects people experience when digesting other forms of protein.
Additionally, the process of hydrolysing allows collagen peptides to dissolve in water, again making it a practical and easy-to-use supplement that can be added into everyday foods, such as smoothies or water.
This is similar to how you would use many workout supplements on the market; for more information regarding products to enhance your atheltic performance, check out OriGym's shortlist of the best pre workout supplements.
#4 Relieves Joint Pain
Another of the most popular health benefits of collagen supplements is their ability to protect the joints.
We have previously explained that joint pains are a natural side effect to our body’s collagen levels decreasing as we age. The reason for this is that collagen, more specifically type 2 collagen, is an important component of cartilage (the tissue that cushions and support joints) and as we get older, this tissue wears and decreases.
The result of this decrease is often joint pain or even arthritis, and this process can occur at a much more rapid pace in athletes. Collagen works to maintain the integrity of your cartilage.
A number of studies have proven that supplementing with collagen can help reduce joint pain, as well as specific symptoms of osteoarthritis (a condition that causes joints to become painful and stiff). Looking specifically at how collagen can benefit athletes, a 2008 study took a subject group of 147 athletes with existing joint pain related to athletic activity and gave half of them a supplementation of collagen hydrolysate over the course of 24 weeks.
The results showed that the group who received the collagen hydrolysate supplement experienced a much greater reduction in joint pain in comparison to the placebo group, both at rest and when walking.
By minimising joint pain, it can enhance fitness performance by promoting more mobility and the overall ability to exercise and perform exercises to a better standard.
If you want to try taking a collagen supplement for its potential pain-relieving effects, studies suggest you should start with a daily dosage of 8–12 grams; it may also be worth making yourself familiar with our common weightlifting injuries and prevention guide to further reduce the liklihood of joint issues.
#5 Promotes Heart Health
Promoting a healthy cardiovascular system is perhaps one of the most overlooked health benefits of collagen tablets, despite being one of the most impressive.
It is said that collagen supplements could potentially have the ability to reduce the risk of heart-related diseases, such as coronary artery disease and atherosclerosis.
Collagen provides structure to your arteries, which are the blood vessels that carry blood from your heart to the rest of your body. Without it, or with a significant lack of it, the arteries could become weak or damaged.
Weak and fragile arteries can lead to a number of more serious issues, such as atherosclerosis, a disease characterised by the buildup of fats, cholesterol and other substances in and on your artery walls which can cause restricted blood flow.
Furthermore, atherosclerosis can lead to the likes of a heart attack and stroke, so minimising the chances of this by increasing collagen intake is beneficial. If you're looking to keep a closer eye on your heart activity, you may find our study that explored How Accurate are Wearable Heart Rate Monitors a good read.
In a 2017 study published in The Journal of Atherosclerosis and Thrombosis, a subject group of 31 healthy adults supplemented with 16g of collagen every day for a six month period. According to the results, the subjects showed significant reduction in measures of artery stiffness by the end of the trial, confirming that collagen can improve heart health and prevent heart-related disease markers.
Additionally, the study also highlighted that levels of HDL, commonly referred to as good cholesterol increased by an average of 6%. HDL is a leading factor in the risk of heart problems, including atherosclerosis, again supporting the theory that collagen benefits heart health.
While more studies are required to confirm the benefits of taking collagen supplements for heart health, researchers believe that the protein may help fortify blood vessel walls to reduce the risk of artery disease and improve overall cardiovascular health.
#6 Improves Gut Health
While the scientific research surrounding this point is minimal, collagen is regularly suggested by health practitioners and experts to help improve gut health and assist gut-related issues, such as leaky gut syndrome and irritable bowel syndrome.
Collagen contains two key amino acids: proline and glycine, as well as lower levels of glutamine, all of which offer benefits to the intestinal tract as well as the stomach and can reduce gut problems and the symptoms associated with them.
Collagen also helps to ensure there is enough acid within the body to enable proper digestion. This has been proven to have a positive effect in regulating the secretion of gastric juices (also known as stomach acid, which is digestive fluid formed within the stomach lining).
As well as regulating gastric acids, collagen also shows promising results in preventing excess amounts of it forming in the stomach.
Having excessive amounts of gastric juices within the body can lead to issues such as stomach ulcers, heart burn and a number of other uncomfortable and painful problems that form as a result of an overly acidic environment.
A number of studies have looked into how collagen benefits specific digestive problems within the gut. For instance, it has built a strong reputation as a potential aid for irritable bowel disease (IBD), a common disorder that affects the large intestine and digestive system.
According to an early study published in the Journal of Clinical Pathology, researchers identified that collagen type 4 levels are generally decreased in patients with ulcerative colitis (UC) and Crohn's disease (CD) - both of which are included within IBD.
Collagen is a fundamental part of the connective tissue which makes up your colon and GI tract. It is an essential building block for ensuring the integrity of a damaged intestinal lining, so by increasing your levels of collagen, it may help create a supportive environment for your body to heal.
For an alternative supplement that also offers assistance to the body's gut health, why not give L-Glutamine a try? One of the primary roles of this amino acid is its prevention of infections and inflammation in the gut.
Overall, while more conclusive evidence is needed to support this view, the benefits of collagen supplements for gut health are promising.
#7 Prevents Bone Loss
We’ve established that collagen makes up a significant amount of structure in the body, and this applies most particularly to the bones.
Collagen is primarily what keeps the bones strong, and just like with muscle mass and skin health, that bone mass naturally decreases with the decline in collagen we experience with age. This is especially true after menopause.
Deterioration of bone mass can lead to complex conditions, such as osteoporosis, which we mentioned earlier and describes low bone density, as well as a higher risk of bone fractures.
Medical research has discovered that supplementing with collagen can benefit bone related conditions by inhibiting the bone breakdown that leads to osteoporosis.
This is supported by the findings of multiple studies, including a 2014 study published in the Journal of Medicinal Food, which discovered that postmenopausal women who took a 5g supplement of collagen every day for 12 months encountered higher blood levels of proteins which promote bone breakdown, as opposed to those who took a combination of collagen and calcium.
This shows promising results for the theory that the use of collagen can reduce bone loss in osteopenic postmenopausal women.
These results are promising, but more human studies are needed before the benefits of collagen supplements in bone health can be confirmed. For an alternative, more active, method of preventing this natural decrease, there is research suggesting that one of the benefits of deadlifts is its ability to increase bone density - you can read more in our thorough guide.
While additional research is necessary to completely confirm the benefits that collagen has on promoting strong bones, the implications suggest taking collagen supplements may help prevent the deterioration of bone density and strength.
Collagen Side Effects
To date, there has been limited testing into the safety of collagen and no research has been conducted into the potential risks of collagen supplements in pregnancy, breastfeeding, children and those with medical conditions or prescribed other medications. This is important to bear in mind if you are considering taking collagen.
Though the risks of collagen are both rare and mild, it is worth noting that the following side effects have been reported when the protein has been consumed in large quantities:
- A lingering unpleasant taste
- A feeling of heaviness in the stomach
An obvious note for those who are allergic to collagen or its source is to avoid it, as taking it could induce an allergic reaction. Besides these risks, which are extremely rare and often mild, taking collagen supplements should not pose any significant health risks in most healthy adults.
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Currently, there are no official guidelines provided by health professionals regarding a safe amount of collagen to take, or an ideal amount to best achieve the health benefits of collagen supplements.
However, depending on the intended use and goal, supplement brands suggest that the dosage will vary.
For skin health and cosmetic benefits, the suggested dosage sits between 2.5 - 10g of hydrolysed collagen again for at least a 12 week period.
However, a study conducted by Skin Pharmacology and Physiology stated that dosages as little as 2.5-5g of protein a day for just four weeks were found to be successful in increasing skin elasticity in elderly women.
Taking collagen supplements for its potential of relieving joint pain and discomfort, it is advised to consume a daily dosage of between 8-12g, which is said to be well-tolerated for up to six months of use.
Of course, collagen supplements will feature a suggested daily dosage printed on the packaging. Many powdered supplements on the market often suggest taking 1–2 scoops (or tablespoons) daily, whereas Holland & Barrett’s Collagen tablets recommend users take between three to five tablets daily; which going off their collagen content of 1000mg (1g) per tablet, implies a dosage of between 3 - 5g of collagen a day is safe.
When to Take Collagen?
While there is no conclusive best time to take collagen as there is with other supplements, some supplement brands do suggest that taking it on an empty stomach allows for the best results.
As collagen is a protein, some people opt to add it into their midday snack or after meals in order to achieve a sense of fullness for longer periods of time, however this has not been confirmed to be effective.
There are reports that suggest activating its joint relief benefits, then taking collagen supplements approximately one hour before exercise is most effective.
The truth is, collagen is beneficial to take at any point of the day, particularly for the health benefits of collagen tablets and supplements outlined within this article. The stomach can absorb collagen no matter the time of day and whether it is taken with or without food; so you can incorporate it into a routine which is most convenient for you.
Food Sources of Collagen
The nutrients in our body play a vital role to our health, as well as our youthfulness; collagen especially.
While our body naturally forms collagen, after the age of 25 this formation starts to slow down significantly and continues to do so the older we get. That is why it is important to ensure we are combating that decrease with supplements and organic food sources to continue reaping the collagen health benefits.
As well as eating foods specifically high n collagen, it has been highlighted that eating foods rich in vitamin C and amino acids can also increase the levels of collagen in the body, OriGym's article on the best vitamins for energy explains this further.
Collagen sources come in different forms and can work differently within the body. For instance, many reports suggest that the best collagen-boosting food source is bone broth/stock as it is a bioavailable form of collagen that your body can utilise right away.
Bone broth draws collagen out of meats such as beef, chicken or fish bones, leaving a liquid that can be drunk or used in a number of dishes.
While the benefits of taking collagen supplements offer equally effective advantaged, alternative food sources of collagen include:
- Egg whites
- Cashew nuts
- Red and yellow vegetables (tomatoes, bell peppers, etc)
- Citrus fruits and berries
- Leafy greens
Additionally, the collagen diet is a method particularly popular amongst beauty enthusiasts as it offers an eating plan consisting of foods high in collagen with the intended goal to improve skin, nails, hair and other aspects of physical appearance.
Though it has not been confirmed by science, the collagen diet has the backing of those who have participated in it and recorded positive results and a number of improved collagen health benefits.
Nutritional Value of Collagen
While this can depend on the chosen supplement, we have provided the nutritional information of a popular product on the market for your reference:
MyProtein Collagen Powder (grape flavour): Per serving (1 scoop = 23g)
- Calories: 73
- Collagen: 20g
- Protein: 18g
- Fat: 0g
- Carbohydrates: 0.3g
- Sugar: 0g
- Salt: 0.4g
What Fitness Goals Are Assisted by Collagen?
While collagen is generally associated with cosmetic benefits, such as the collagen benefits of hair, nails and youthful skin, we previously mentioned that it’s a supplement that is slowly increasing in popularity within the fitness world.
This comes as a result of its potential benefits for reduced joint pain and increased muscle mass - as we have mentioned both of these points in thorough detail with the article, we won’t repeat ourselves, but allow us to briefly recap how these health benefits of collagen tablets and supplements could enhance your fitness performance.
Enhances athletic performance by reducing joint pain
Natural decrease in collagen sees the tissue that cushions joints lessen as we age; a process that occurs more rapidly in athletes. Studies using athletes as subjects found that collagen supplements can reduce joint pain caused by athletic activities; you can read more about this in our report on cardio & aerobic exercise benefits.
This reduction can speed up recovery time as well as allow for enhanced athletic performance without pain and fatigue. Enhanced athletic performance is one of the most popular collagen benefits in bodybuilding.
Improves muscle mass
Collagen is an important component of muscles. One reason that muscle mass decreases with age is that collagen decreases. Research has already proven that collagen supplements can reverse this aging trend in people diagnosed with sarcopenia, age-related muscle loss. Improved muscle mass is amongst the most popular collagen benefits for men and bodybuilding.
How To Supplement With Collagen?
Collagen supplements typically appear in two forms; capsule and powder.
Generally speaking, it may be more cost effective to go with a powdered version, ensuring that the product is hydrolysed collagen.
You may also find that some manufacturers use undenatured collagen, which will appear in much smaller dosages but has been shown to be somewhat equally effective to hydrolysed collagen in the studies included here.
Collagen powders can be purchased in a variety of flavorus, making them great options to add into water and other beverages.
Whatever way you choose to consume, collagen health benefits can be achieved through all formations of the supplement.
Where to Buy Collagen?
Due to the rise in demand for collagen, with the collagen health benefits gaining more popularity, collagen supplements are becoming widely available across most healthcare and supplement brands.
We always recommend purchasing supplements from a reputable brand to ensure you know what you are putting into your body.
There has been a huge boom in recent years of small brands popping up on social media, however, unless you can confirm that these companies are legitimate and safe, we recommend the following names for your collagen supplements who hold a prestigious name in the supplement industry:
What Can Influence The Turnover And Production Of Collagen?
Collagen turnover and production changes and decreases throughout our lifespan naturally. In fact, aging is the primary cause behind collagen degradation.
The benefits of collagen supplements can be cancelled out as a result of a number of other influences, including: smoking, UV radiation exposure, certain diseases (such as arthritis), menopause, hormone replacement therapy, bodyweight and nutrient deficiencies.
Let us explain:
As mentioned, ageing is the primary cause of collagen degradation. As we age, cumulative effects of oxidative stress alter the structure of the collagen proteins. This in turn leads to a loss of a function. Additionally, as we age, we produce less collagen which may impact larger structures.
Smoking affects collagen much in the same way as ageing, altering collagen structures and decreasing the synthesis of type 1 and 3 collagen proteins.
Ultraviolet (UV) radiation
Exposure to UV radiation appears to also negatively impact the structure of collagen (accelerating the breakdown of collagen via pathways related to peptide cleaving). Interestingly, other forms of irradiation, such as those used in the treatment of certain cancers, may stimulate collagen synthesis.
Certain diseases can also lead to collagen degradation and disruption of production. These may be heritable disorders of connective tissue imparted by your genetic makeup. Connective tissue diseases can also be caused by things that exist in the environment and your state of health.
Infection by potentially harmful pathogens may also lead to accelerated collagen degradation.
Studies have shown that up to 30% of dermal collagen may be lost in the first 5 years after menopause, and collagen decreases by approximately 2.1% per year. Experimental data has shown that the presence of oestrogen may actually protect cells against oxidative damage.
Post-menopause is a time where oestrogen levels are in significant decline, so many explain as to why we see this rapid degradation in collagen proteins.
Hormone replacement therapy may be a possible solution; it could never be advocated as a form of skin therapy. The use of topical treatments may be a potential alternative, however more work needs to be done to further evaluate efficacy and safety.
Bodyweight and type 2 diabetes
Obesity may also lead to collagen degradation and alterations in production. Fibrosis is a hallmark of metabolically dysfunctional adipose (fat) tissue and is produced as a result of rapid adipose tissue growth and the inability to meet this pace.
This will eventually lead to undesired tissue remodelling and loss of flexibility and tissue plasticity, which ultimately leads to adipocyte dysfunction.
Adipocyte dysfunction can lead to a pro-inflammatory state which carries many health consequences, including further damage to collagen structures.
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As you can see, the health benefits of collagen supplements are vast, ranging from improved skin health and reduced wrinkles to less joint pain and bone loss. Plus, there are even more that do not have significant science backing behind them at this point in time.
What’s more, there are few side effects reported as a result of collagen, and the once suggested are extremely mild, making this a truly safe supplement to add into your life.
While your body can’t distinguish whether the protein you consumed came from chicken, poultry or a hydrolysate collagen supplement, it does make a difference to how the body digests the protein. Collagen supplements make the amino acids more easily available to your tissues - making this an ideal source of protein.
Before you leave, if learning about collagen supplement benefits and their impact on the human body has interested you, you would certainly benefit from delving further into human anatomy and how different supplements can affect our health.
Check out OriGym’s Level 4 Advanced Sports Nutrition qualification, where you can turn your interest into a successful career as a nutritionist.
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- Zdzieblik D, Oesser S, Baumstark MW, Gollhofer A, König D. Collagen peptide supplementation in combination with resistance training improves body composition and increases muscle strength in elderly sarcopenic men: a randomised controlled trial. Br J Nutr. 2015;114(8):1237-1245. doi:10.1017/S0007114515002810.
- Bolke L, Schlippe G, Gerß J, Voss W. A Collagen Supplement Improves Skin Hydration, Elasticity, Roughness, and Density: Results of a Randomized, Placebo-Controlled, Blind Study. Nutrients. 2019;11(10):2494. Published 2019 Oct 17. doi:10.3390/nu11102494.
- Oertzen-Hagemann V, Kirmse M, Eggers B, et al. Effects of 12 Weeks of Hypertrophy Resistance Exercise Training Combined with Collagen Peptide Supplementation on the Skeletal Muscle Proteome in Recreationally Active Men. Nutrients. 2019;11(5):1072. Published 2019 May 14. doi:10.3390/nu11051072.
- Tomosugi N, Yamamoto S, Takeuchi M, et al. Effect of Collagen Tripeptide on Atherosclerosis in Healthy Humans. J Atheroscler Thromb. 2017;24(5):530-538. doi:10.5551/jat.36293
- Koutroubakis IE, Petinaki E, Dimoulios P, Vardas E, Roussomoustakaki M, Maniatis AN, Kouroumalis EA. Serum laminin and collagen IV in inflammatory bowel disease. J Clin Pathol. 2003 Nov;56(11):817-20. doi: 10.1136/jcp.56.11.817. PMID: 14600124; PMCID: PMC1770111.
- Elam ML, Johnson SA, Hooshmand S, Feresin RG, Payton ME, Gu J, Arjmandi BH. A calcium-collagen chelate dietary supplement attenuates bone loss in postmenopausal women with osteopenia: a randomized controlled trial. J Med Food. 2015 Mar;18(3):324-31. doi: 10.1089/jmf.2014.0100. Epub 2014 Oct 14. PMID: 25314004.
- Proksch E, Segger D, Degwert J, Schunck M, Zague V, Oesser S. Oral supplementation of specific collagen peptides has beneficial effects on human skin physiology: a double-blind, placebo-controlled study. Skin Pharmacol Physiol. 2014;27(1):47-55. doi: 10.1159/000351376. Epub 2013 Aug 14. PMID: 23949208.