Collagen

Collagen is the most abundant protein in the body. It plays many important roles, including maintaining the structure of skin and joints and supporting blood clotting. In recent years, collagen has become increasingly popular as a dietary supplement and as an ingredient in shampoos and body lotions. But what exactly is collagen and what is it good for? This article provides an overview of the most important properties of collagen.

What is collagen?

Collagen is the most abundant protein in the human body and makes up around a third of all proteins in the body. Collagen is one of the most important building blocks of bones, skin, muscles, tendons and ligaments. It is also found in many other parts of the body, including blood vessels, the cornea and teeth. You can think of collagen as a kind of "glue" that holds all these things together. In fact, the term collagen comes from the Greek word "kólla", which means glue.

What does collagen do in the body?

There are at least 16 types of collagen. The four main types are type I, II, III and IV (1). These four main types play the following roles in the body:

• Type I: This type makes up 90% of the body's collagen and consists of tightly packed fibers. It provides the structure for skin, bones, tendons, cartilage, connective tissue and teeth.
• Type II: This type consists of more loosely packed fibers and is found in the elastic cartilage that cushions the joints.
• Type III: This type supports the structure of muscles, organs and arteries.
• Type IV: This type helps with filtration and is found in the layers of the skin.

With increasing age, the body produces less and less collagen and the quality of the collagen also decreases. One of the visible signs of this is the skin, which becomes less firm and supple. Joint cartilage also becomes weaker with increasing age.

Nutrients that increase collagen production

All collagen begins as procollagen. The body produces procollagen by combining the two amino acids glycine and proline. Vitamin C is needed for this process. You can help the body produce this important protein by ensuring you consume sufficient amounts of the following nutrients:

• Vitamin C: Large amounts of vitamin C are found in citrus fruits, peppers and strawberries (2).
• Proline: Large amounts are found in egg whites, wheat germ, dairy products, cabbage, asparagus and mushrooms (3).
• Glycine: Large amounts are found in pork rind, chicken skin and gelatine. Glycine is also found in many other protein-containing foods (4).
• Copper: Large amounts are found in offal, sesame seeds, cocoa powder, cashews and lentils (5, 5).

In addition, the body needs high-quality proteins that provide all the amino acids needed to make new proteins. Meat, poultry, seafood, dairy products, legumes and tofu are all excellent sources of these amino acids.

• Summary: Four of the nutrients that help with collagen production are vitamin C, proline, glycine and copper. Eating high quality proteins provides the body with the amino acids it needs for collagen production.

Things that can damage collagen

Perhaps even more important is to avoid the following collagen-destroying behaviors:

• Excessive consumption of sugar and refined carbohydrates: Sugar interferes with collagen's ability to repair itself. For this reason, the consumption of sugar and refined carbohydrates should be minimized (7).
• Too much sun: Ultraviolet radiation can reduce collagen production. For this reason, excessive sunbathing should be avoided (8).
• Smoking: Smoking reduces collagen production. This can impair wound healing and lead to wrinkles (9).

Some autoimmune diseases such as lupus can also damage collagen. Summary: You can help your body preserve and protect its collagen by avoiding certain behaviors that can damage collagen. These include excessive sugar consumption, smoking and sunburns.

Natural food sources of collagen

Collagen is found in the connective tissue of animal foods. It is found in large quantities in the skin of pigs and poultry, for example. A particularly rich source of collagen is bone broth, which is made by boiling the bones of poultry and other animals. Gelatine is basically boiled collagen. Gelatine is therefore very rich in the amino acids needed for collagen production. However, there is debate as to whether eating collagen-rich foods actually increases the amount of collagen in the body. When you eat animal protein, it is broken down into amino acids which are then reassembled into new proteins in the body, meaning that the collagen you eat will not directly lead to larger amounts of collagen in the body.

• Summary: Animal products such as bone broth, gelatin, chicken skin and pig skin are very rich in collagen.

Benefits of collagen supplements

Two types of supplement are becoming increasingly popular: hydrolyzed collagen (collagen hydrolysate) and gelatin. Gelatine is produced when collagen is cooked. With collagen hydrolysate, the larger proteins have already been broken down into smaller peptides that are more easily absorbed by the body.

There are not many studies that have been done on collagen supplements, but the ones that do exist point to benefits in the following areas:

• Muscle mass: a 2015 study conducted on older men showed that a combination of collagen peptide supplements and strength training increased muscle mass and strength more than a placebo (10).
• Arthritis: In another study, supplements were administered to people suffering from osteoarthritis. These subjects experienced a significant reduction in pain over the course of the 70-day study compared to subjects who received only a placebo (11).
• Skin elasticity: Women who took a collagen supplement experienced an improvement in skin elasticity in a 2014 study. Collagen is also used in products that are applied to the skin to improve the appearance of the skin by minimizing wrinkles (12, 13).

Some alternative medicine practitioners also advocate the use of collagen supplements to treat a pathologically permeable gut wall. Summary: Studies suggest that collagen supplements may help improve skin texture, increase muscle mass and reduce osteoarthritis pain.

What are the health benefits of collagen supplementation?

Consuming collagen can provide a range of health benefits, from improving skin health to relieving joint pain (14, 15). Below, we'll take a closer look at some of these health benefits and the scientific evidence supporting them.

Collagen can improve skin health

Collagen is an important component of the skin. It plays a role in strengthening the skin and also promotes skin elasticity and hydration. As you age, your body produces less collagen, which causes the skin to become drier and wrinkles to form (16). Several studies have shown that collagen peptides or supplements containing collagen can help slow down skin ageing and reduce dryness and wrinkles (1, 18, 19, 20). In one study, women who took a supplement containing 2.5 to 5 grams of collagen for eight weeks experienced less skin dryness and increased skin elasticity compared to women who did not take the supplement (19). Another study found that women who consumed a drink mixed with a collagen supplement for 12 weeks showed increased skin hydration and a significant reduction in wrinkles compared to the control group (18).

The wrinkle-reducing effects of collagen supplements are attributed to their ability to stimulate the body to produce more collagen (16, 17). In addition to this, taking collagen supplements may promote the production of other proteins including elastin and fibrillin, which are important for skin structure (16, 17).

There are also many anecdotal reports that collagen supplements are helpful in preventing acne and other skin conditions, but these are not supported by scientific research.

• Summary: Taking collagen supplements may be helpful in slowing skin aging

Collagen can help relieve joint pain

Collagen helps maintain the integrity of articular cartilage - the rubbery tissue that protects joints. As the amount of collagen in the body decreases with age, the risk of developing degenerative joint diseases such as osteoarthritis increases (21). Some studies have shown that taking collagen supplements can help alleviate symptoms of osteoarthritis and relieve general joint pain (14, 21). In one study, 73 athletes who took 10 grams of collagen per day for 24 weeks experienced a significant reduction in joint pain while walking and at rest compared to the control group who did not take collagen (22). In another study, adults took two grams of collagen per day for 70 days. The subjects who took collagen reported a significant reduction in joint pain and were better able to participate in physical activities than those who did not take collagen (12). Scientists suspect that supplemented collagen accumulates in the joint cartilage and stimulates the body to produce collagen. They also believe that collagen may contribute to reductions in inflammation, better joint support and reduced pain (23). When taking collagen supplements to relieve joint pain, studies suggest that you should start with a dose of 8 to 12 grams per day (21, 24).

• Summary: Taking collagen supplements has been shown to reduce inflammation and stimulate collagen synthesis in the body. This may help relieve joint pain in joint conditions such as osteoarthritis.

Collagen could prevent loss of bone mass

Bones are mainly made up of collagen, which gives them their structure and helps to keep them strong and stable (25). When collagen deteriorates with age, the same happens to bone mass. This can lead to conditions such as osteoporosis, which is characterized by low bone density and is associated with a higher risk of fractures (25, 26). Studies have shown that taking collagen supplements has certain effects on the body that help inhibit the bone loss that leads to osteoporosis (21, 24). In one study, women took either a calcium supplement in combination with 5 grams of collagen or a calcium supplement without collagen over a 12-month period. At the end of the study, the women who had taken the calcium and collagen supplement showed significantly lower blood levels of proteins that promote bone loss compared to the women who had taken calcium alone (27). Another study of 66 women who took 5 grams of collagen over a 12-month period came to similar conclusions. The women who took the collagen showed a 7% increase in their bone mineral density compared to the women who did not take collagen (28). Bone mineral density is a measure of the amount of minerals such as calcium in the bones. Low bone mineral density is associated with weak bones and the development of osteoporosis (29). These results are promising, but further human studies are needed to confirm the role of collagen supplements in bone health.

• Summary: The consumption of collagen supplements may help reduce the risk of bone-related conditions such as osteoporosis. These supplements have the potential to increase bone mineral density and lower levels of proteins in the blood that stimulate bone loss.

Collagen supplements could increase muscle mass

Between 1 and 10% of muscle tissue is made up of collagen. This protein is necessary to keep muscles strong and maintain proper muscle function (30). Studies suggest that collagen can increase muscle growth in people suffering from sarcopenia - an age-related loss of muscle mass (31). In one study, 27 frail men participating in an exercise program consumed 15 grams of collagen per day for 12 weeks. Compared to the men who exercised but did not take a collagen supplement, these men saw significantly greater gains in muscle mass and strength (31).

Scientists believe that taking collagen may promote the synthesis of muscle proteins such as creatine and may also stimulate muscle growth after training (31). However, more studies are needed to investigate the potential muscle-building properties of collagen.

• Summary: Scientific research has shown that the consumption of collagen supplements can promote muscle mass and strength in people with age-related muscle loss.

Collagen promotes heart health

Scientists have theorized that taking collagen supplements may help reduce the risk of heart-related diseases. Collagen gives the arteries - the blood vessels that carry blood from the heart to the rest of the body - their structure. Without sufficient amounts of collagen, arteries can become weak and unstable (32). This can lead to atherosclerosis - a disease characterized by narrowing of the arteries. Atherosclerosis can potentially lead to heart attacks and strokes (33). In one study, 31 healthy adults consumed 18 grams of collagen for six months. At the end of the study, a significant reduction in arterial stiffness was observed in all subjects compared to before the study (34). In addition, an increase in the levels of "good" HDL cholesterol by an average of 6% was observed. HDL cholesterol levels are an important factor in the risk of heart disease, including arteriosclerosis (34). Despite these promising study results, more studies are needed to further investigate the role of collagen supplements in heart health.

• Summary: Taking collagen supplements could help reduce risk factors associated with heart disease such as atherosclerosis.

Other health benefits

Collagen supplements may have other health benefits, but these have not yet been studied extensively:

• Hair and nails: Taking collagen could increase the stability of nails by preventing brittleness. In addition, collagen may encourage your hair and nails to grow longer (35).
• Digestive health: Although there is no scientific research to confirm this, some doctors advocate the use of collagen supplements to treat a pathologically permeable intestinal wall.
• Brain health: No studies have yet investigated the role of collagen supplements in brain health. However, some people report improved mood and reduced symptoms of anxiety.
• Weight loss: Some people believe that collagen supplements can promote weight loss and a faster metabolism. However, there are no studies to support these claims.

Although these potential effects are promising, scientific research is needed before formal conclusions can be drawn.

• Summary: It is claimed that collagen supplements may promote brain, heart and digestive health, as well as helping to control weight and maintain healthy skin and hair. However, there is still no scientific evidence to support these effects.

Safety and side effects

To date, there is no very reliable information regarding the safety and efficacy of collagen supplements. The potential side effects of gelatin supplements include a lingering bad aftertaste and a feeling of heartburn. In addition, collagen supplements can cause digestive side effects such as bloating and heartburn (24). In addition, allergic reactions may occur if you are allergic to the source of the supplement.

How to supplement

Collagen peptides are available in powder form and can be easily added to other foods. The peptides do not form a gel, so you can add them to smoothies, soups or baked goods without affecting their texture. You can also use gelatine to make homemade gummy bears.

Other applications

Collagen has many applications, ranging from food to medicine to the production of other things. For example, collagen has been used for thousands of years to make glue. Even today, collagen is used to make strings for musical instruments.

In foodstuffs, collagen is heated to produce gelatine and collagen is also used in the production of sausage casings. In the medical field, collagen is used as a filler in plastic surgery and as a coating for severe burns.

Conclusion

Collagen is an important protein that gives structure to many parts of the body. Interestingly, the foods and nutrients you eat can help your body produce this protein. Alternatively, collagen supplements can also be useful. Some preliminary studies show that these supplements may improve skin quality and muscle function and relieve pain associated with osteoarthritis.

References

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