Collagen – to supplement or not to supplement? Check out what research says!

What is collagen?

Collagen is the main structural protein of all animal organisms. It is an extremely durable structure found in virtually all tissues, giving them stretch and elasticity. Collagen proteins make up about 30% of all human proteins. Collagen is particularly abundant in the skin, tendons and bones, but it is also found in cartilage, blood vessels and gums. Although collagen is usually referred to in the singular, it is not one specific protein – there are many types of collagen that differ in structure, fiber length, amino acid composition and functions.

The collagen in the body is the same collagen found in animal food – which means it can be eaten and supplemented. It belongs to a group of nutrients known as low value proteins, which do not contain several key amino acids. The collagen particle consists of two main amino acids: proline (approx. 10%) and glycine (approx. 33%), as well as smaller amounts of hydroxylysine and hydroxyproline.

Collagen is produced naturally in the body from amino acids (supplied in food with proteins). Vitamin C also plays a very important role in the production of collagen in the body. Its extreme deficiency can manifest itself as scurvy, a multi-organ disease causing, for example, abnormal bone development, slow wound healing or weakening of the gums. All these symptoms are actually caused by the weakening of collagen structures. Vitamin C is an extremely important substance when it comes to proper collagen synthesis.

The efficiency of collagen production in the body decreases with age, a process whose effects first become visible around the age of 18-29. After the age of 40, collagen synthesis efficiency decreases by about 1% per year. External factors have a great impact on the production of collagen. It is weakened by:

• excessive exposure to the sun and UV radiation,
• tobacco use,
• lack of sleep,
• insufficient physical activity,
• excessive consumption of alcohol,
• low value diet poor in antioxidants.

Adequate collagen production in the body is crucial for staying healthy and keeping fit. Collagen affects:

• the firmness and condition of the skin,
• bone elasticity (which prevents fractures),
• the condition of articular cartilage,
• blood vessel elasticity,
• the condition of hair and nails,
• the condition of the gums and dentition.

More efficient collagen production in the body (potentially) means better condition and appearance of the skin, lower risk of injury and faster regeneration. However, collagen synthesis is quite a complicated process and does not rely on ingested collagen being built into the collagen structure of the body. Collagen is too large a particle to be directly absorbed and circulated in the bloodstream after being eaten, and then to be simply picked up by the cells that need it. Dietary collagen is broken down in the stomach into amino acids and peptides. For this reason, a lot of controversy has arisen around the legitimacy of collagen supplementation. We will explain this below.

Does collagen supplementation make sense? Potential mechanisms

The collagen proteins in the human body and those supplied with food or supplements are practically the same chemical particles. However, this does not mean that if you do not eat collagen, your body will not produce it. Collagen is formed from amino acids, which are provided by all sources of protein – both of animal and plant origin. For many years, it was believed that collagen supplementation did not make sense, because the same effect could be achieved by eating any protein-rich products. However, latest research indicates that dietary collagen has several unique properties and can better stimulate collagen synthesis in the body than a protein supplement or protein-rich food. Why is that? Scientists have identified three potential mechanisms:

1. Collagen is valuable because of its glycine and proline content

Dietary collagen primarily provides two amino acids: – glycine and proline. They are quite common in food and can be found in every protein product. However, collagen is an extremely good source of these amino acids. There is about 29 g of glycine and 9 g of proline in 100 g of collagen.

For comparison, here is the glycine and proline content in several good protein sources:

• 100 g of natural yogurt contains about 0.1 g of glycine and 0.4 g of proline;
• 100 g of grilled chicken breast contains about 1.4 g of glycine and 1 g of proline;
• 100 g of ground beef contains ca. 1.2 g of glycine and 0.9 g of proline;
• 100 g of tofu contains about 0.4 g of glycine and 0.6 g of proline;
• 100 g of protein supplement contains ca. 1.4 g of glycine and 4.4 g of proline.

Collagen is a great source of amino acids for the formation of collagen structures in the body. This is one of the potential mechanisms underlying its positive effect on the synthesis of collagen structures.

2. Hydroxylated amino acids from collagen are the most valuable

Collagen is also a source of hydroxylated amino acids (hydroxyproline and hydroxylysine). Chemically, these are amino acids with the –OH group. They determine the stiffness of collagen structures and are necessary for the formation of tendons, bones or skin structures.

The body is able to subject amino acids to the hydroxylation process, i.e. it can obtain hydroxyproline from proline and hydroxylysine from lysine. Most likely, however, it is more efficient for the body to obtain already hydroxylated amino acids from food (or supplements). They can be directly incorporated into various structures and potentially improve the formation of collagen structures. This is another potential mechanism which drives the positive effects of dietary supplementation of collagen on the efficiency of collagen structure formation.

3. Collagen provides bioactive peptides

Theoretically, each protein supplied with food in the process of digestion should be broken down into the smallest units – amino acids. In practice, however, some of the proteins are not fully digested. Proteins are broken down into amino acids and peptides, i.e. larger particles made up of several amino acids that are clumped together. Some peptides can be absorbed into the bloodstream and, in this form, play a significant role in the body.

In the case of collagen, several different peptides can be formed during digestion:

• di-peptides (from two linked amino acids), such as hydroxyproline-proline or hydroxyproline-glycine,
• tri-peptides (consisting of three linked amino acids), such as glycine-proline-hydroxyproline.

The appearance of collagen peptides in the bloodstream can be a signal to the body that the collagen structure has been damaged and should be rebuilt. Peptides can therefore be a stimulus to activate the production of collagen structures. In fact, the peptide has been supplied from the outside (e.g. in the form of a collagen supplement), but the effect of stimulating collagen building is achieved. 

Practical advice: All of the three potential mechanisms of action of collagen taken with supplements or food can occur simultaneously. Scientists have yet to unequivocally conclude which of them has the greatest impact on the human body. However, the mechanism of action is of secondary importance. Scientific studies have also shown the positive effects of collagen in practice.

Collagen and its “anti-aging” effects on the skin

In recent years, several groundbreaking studies have been carried out that have changed the perception of collagen and convinced many experts that in some cases it is really worth recommending. First of all, it has been proven that collagen has a positive effect on the musculoskeletal system, i.e. on the joints, regeneration after injuries and overloads, and wound healing after surgeries.

Current research also indicates that taking collagen can be an effective way to improve skin condition, delay the aging process, and even partially reverse the symptoms of skin aging.

The study, which was one of the first to point out these properties, involved 69 women aged 35-55. The participants were divided into a control group, which received a placebo, and a research group, which took 2.5 g or 5 g of collagen for 8 weeks. After just 4 weeks, an increase in collagen density in the dermis was observed in women who took the supplement, and after 8 weeks – better skin hydration became evident.

Another study examined the effect of fish collagen supplementation on the skin condition of women aged 45-60. In the women in the study group, the following were observed:

• improved skin suppleness,
• improved skin radiance,
• greater skin elasticity,
• less visible wrinkles.

A similar effect of supplementation has also been confirmed by other studies. The most frequently mentioned effect of collagen supplementation is a general increase in skin elasticity, which is especially important when you want to delay the symptoms of aging. Additional benefits include less perceived dryness and flaking of the skin. Therefore, it can be concluded that in light of the latest research, collagen can actually have an “anti-aging” effect.

Individual studies used various methods to assess the effects of supplementation. Sometimes these were questionnaires, other times a comparison of skin healing time after treatments or measurements of skin echogenicity. Most studies, regardless of the methods used, have actually revealed positive effects. They can be expected after about 4-8 weeks of regular supplementation with the right dose.

Practical hints: The doses of collagen that will potentially have an “anti-aging” effect are from 2.5 to 10 g per day (optimally about 5 g/day). Research shows that positive effects were achieved by using both fish collagen and bovine collagen, as well as collagen in a hydrolyzed form and without hydrolyzation.

Collagen and its impact on joints, bones and the musculoskeletal system

Collagen supplementation also has a positive effect on the musculoskeletal system. This is especially important for active people and athletes. Research reviews suggest that collagen can realistically:

• support the treatment of tendon inflammation,
• reduce joint soreness in athletes,
• strengthen tendons and ligaments,
• accelerate regeneration after an injury,
• improve joint function.

Collagen can be an excellent supplement used during the treatment of injuries, as well as during more intense training periods. Collagen supplementation should be carried out in rotation, with the supplement being taken every day for about 8-12 weeks.

Practical hints: The doses of collagen used to support the musculoskeletal system are higher than those recommended to improve the condition of the skin. Positive effects in studies have been achieved with 10-20 g of collagen (of various types) per day. For the best results, it is recommended to take collagen supplements about 1-2 hours before training. Collagen proteins will be partially digested and absorbed during this time. Thanks to physical activity and increased blood supply to the structures of the locomotor system, they will be distributed faster and more effectively in the body.

How to choose a good collagen supplement?

There are many collagen supplements available on the market. Here are some aspects to consider when choosing collagen:

• Opt for animal collagen (e.g. fish (marine)/beef (bovine)/pork collagen). Although scientists are trying to recreate collagen structures with the participation of plant proteins, their attempts have not yet yielded the desired results. Collagen naturally occurs only in animal tissues. Fish (marine) collagen is better absorbed and bioavailable, while bovine collagen contains more hydroxyproline. Each of them has its own advantages and disadvantages. There is no conclusive evidence that one type of collagen works much better than another, and different types of collagen are often used in studies.
• Avoid fillers. Collagen products often contain additives that can increase the price of the product, without having any clearly proven effectiveness. A good addition to collagen is, for example, vitamin C, which improves its use in the body, but other additives, such as biotin or hyaluronic acid, may be unnecessary.
• Read the list of ingredients carefully. The taste of pure collagen is quite peculiar, so many manufacturers try to diversify the formula to make it milder. Pay attention to what flavors and colorants are added to the collagen product you choose, as well as to how much pure collagen is contained in 100 g of the supplement.
• Choose the hydrolyzed version. Hydrolyzed and freeze-dried collagen is widely available. Hydrolyzed collagen is potentially a better choice because the smaller hydrolysate molecules are absorbed faster.
• Check the dose. If you want an effect that supports skin firmness, the recommended doses of collagen are about 5 g per day. To improve the condition of your joints, muscles, tendons and the entire musculoskeletal system, the optimal dose is about 10-20 g per day. When choosing a collagen product, pay attention to how it is divided into single doses.
• Rely on scientific research. Supplements differ in terms of the molecular weight of collagen particles. A molecular weight of collagen of ca. 2–4 kDa theoretically provides better absorption than larger molecules, but this is not directly reflected in most studies. The same is true of the type of collagen (e.g. collagen type I or II) – according to research, this does not have much clinical significance and does not affect the effects of supplementation. Both types of collagen are digested into the same peptides and/or amino acids.

If you want to achieve a specific effect of collagen supplementation, such as improved skin firmness or regeneration after an injury, it is better to reach for standardized portions of collagen. If you are looking for overall health support, you can get collagen from food, naturally. There is a lot of collagen in chicken legs, broths, animal skins, veins, tendons and cartilage, offal, fish broths, (meat and fish) jellies and fish heads.

Gelatin can also be a source of collagen in the diet. Gelatin is processed collagen that has been subjected to hydrolysis, i.e. simply collagen after thermal treatment. In some studies on the effectiveness of collagen, it was used in the form of gelatin and satisfactory results were achieved. The use of gelatin for cooking can be a good alternative to collagen supplementation.

Although collagen is a natural substance, it can also have disadvantages and contraindications. It is not recommended to use it for more than three months. If you have any doubts, it is best to consult a doctor before starting supplementation.

_References:

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