What is collagen?

Collagen is the most abundant protein in your body. It accounts for about 30% of its total protein. Collagen is the primary building block of your body’s skin, muscles, bones, tendons and ligaments and other connective tissues. It’s also found in your organs, blood vessels and intestinal lining.

Proteins are made from amino acids. The main amino acids that make collagen are proline, glycine and hydroxyproline. These amino acids group together to form protein fibrils in a triple helix structure. Your body also needs the proper amount of vitamin C, zinc, copper and manganese to make the triple helix.

What does collagen do?

Collagen’s main role is to provide structure, strength and support throughout your body.

Collagen’s specific roles include:

  • Helping fibroblasts to form in your dermis (middle skin layer), which helps new cells grow.
  • Playing a role in replacing dead skin cells.
  • Providing a protective covering for organs.
  • Giving structure, strength and elasticity to your skin.
  • Helping your blood to clot.

Are there different types of collagen?

Some 28 types of collagen types have been identified. They differ by how the molecules are assembled, the cell components that are added and where the collagen is used in your body. All collagen fibrils have at least one triple helix structure.

The main five types of collagen and what they do are:

  • Type I. This type makes up 90% of your body’s collagen. Type I is densely packed and used to provide structure to your skin, bones, tendons and ligaments.
  • Type II. This type is found in elastic cartilage, which provides joint support.
  • Type III. This type is found in muscles, arteries and organs.
  • Type IV. This type is found in the layers of your skin.
  • Type V. This type is found in the cornea of your eyes, some layers of skin, hair and tissue of the placenta.

What happens to collagen as I age?

Your body produces less collagen as you age, and existing collagen breaks down at a faster rate. The collagen is also lower in quality than when you were younger. Women experience a significant reduction in collagen production after menopause. It’s normal for everyone to experience a decline in collagen production after age 60.

Can I tell if my body’s collagen level is decreasing?

Collagen can’t be measured — for instance, in a blood test — but there are signs that your collagen level is decreasing. These signs and symptoms include:

  • Skin that’s wrinkled, crepey or sagging.
  • Hallowing in and around your eyes and face.
  • Shrinking, weakening muscles and muscle aches.
  • Stiffer, less flexible tendons and ligaments.
  • Joint pain or osteoarthritis due to worn cartilage.
  • Loss of mobility due to joint damage or stiffness.
  • Gastrointestinal problems due to thinning of the lining of your digestive tract.
  • Problems with blood flow.

What lifestyle habits damage collagen?

Avoid these factors, which can decrease collagen levels in your body:

  • Smoking. Smoking decreases collagen production. It damages collagen and elastin, leading to wrinkles and slow wound healing. Nicotine constricts blood vessels near your skin’s surface, preventing the delivery of oxygen and nutrients.
  • Eating too much sugar and refined carbs. Sugar attaches to proteins to form advanced glycation end products. These molecules damage nearby proteins and cause collagen to become weak, dry and brittle.
  • Exposure to ultraviolet light. Too much sunlight reduces collagen production and caused collagen to break down more rapidly. Ultraviolet sunlight causes wrinkles. Avoid excessive sun exposure and always wear sunscreen (SPF 30 and higher) when you’re outside.

What diseases and other factors damage collagen?

Autoimmune diseases (your body’s immune system attacks its own tissue) can damage collagen. Rheumatoid arthritis, lupus, dermatomyositis and scleroderma are autoimmune, connective tissue diseases known to damage collagen.

Genetic mutations can also damage collagen. Collagen construction errors result in conditions such as Ehlers-Danlos syndrome and osteogenesis imperfecta.

Collagen levels also decline naturally with age.

What can I do to improve skin collagen loss to slow the signs of aging?

To slow the effects of skin aging, wear sunscreen every day. Exposure to ultraviolet light damages collagen. Use products with a sun protection factor (SPF) of 30 or higher. Wear a wide-brimmed hat, sunglasses with UV protection and lightweight long-sleeved shirts and pants while outside. Look for clothing with an ultraviolet protection factor label for extra protection. Avoid tanning beds.

Eat a well-balanced diet, like the Mediterranean diet, which is loaded with vegetables, beans, whole grains, nuts and fruits and a moderate amount of seafood, meats, poultry, dairy and eggs.

How is collagen used in the fields of medicine and cosmetics?

Collagen can be broken down, converted and absorbed back into your body. It has a wide range of uses in medicine and cosmetics. Collagen used for medical purposes comes from humans, cows, pigs or sheep. Uses include:

  • Dermal fillers: Collagen injections can fill out shallow depressions in your skin, such as lines and wrinkles.
  • Wound dressing: Collagen helps wounds heal by attracting new skin cells to the wound.
  • Periodontics: Collagen acts as a barrier to prevent fast-growing gum tissue from developing into a wound in a tooth, giving the tooth cells the time they need to regenerate.
  • Vascular prosthetics: Donor collagen tissue grafts have been used to reconstruct arteries, help regenerate peripheral nerves and make blood vessel prostheses.

Does eating collagen-rich foods increase the collagen level in my body?

Collagen can’t be absorbed by your body in its whole form. Your body breaks down the collagen proteins you eat into amino acids. So eating collagen-rich foods doesn’t directly result in higher collagen levels in your body.

Still, many foods that provide the raw ingredients that support collagen production can be eaten as part of a healthy diet. These foods contain the amino acids proline and glycine. Vitamin C, zinc and copper are also needed for the process. Foods that contain these amino acids, vitamins and minerals include:

  • Vitamin C. Vitamin C is found in oranges, strawberries, bell peppers, broccoli, Brussels sprouts and potatoes.
  • Proline. Proline is found in mushrooms, cabbage, asparagus, peanuts, wheat, fish, egg whites and meat.
  • Glycine. Glycine is found in red meats, turkey, chicken and pork skin, peanuts and granola.
  • Copper. Copper is found in liver, lobster, oysters, shiitake mushrooms, nuts and seeds, leafy greens, tofu and dark chocolate.
  • Zinc. Zinc is found in oysters, red meat, poultry, pork, beans, chickpeas, nuts, broccoli, green leafy vegetables, whole grains and milk products.

What are collagen peptides?

Collagen peptides are small pieces of animal collagen. Collagen can’t be absorbed in a whole form. It has to be broken down into smaller peptides or amino acids. Oral collagen supplements come in the form of pills and powders. They usually contain two or three amino acids. They are sold as collagen peptides or hydrolyzed collagen. Collagen peptides are absorbed through your gastrointestinal tract.

What does the research say about the effectiveness of collagen supplements?

There’s a lack of randomized controlled trials of dietary supplements (the gold standard to test the effectiveness of medications). The few such studies that have been done have found that collagen peptides are possibly effective for improving skin hydration and skin elasticity. It’s also possibly effective for relieving pain and improving joint function in people with knee osteoarthritis.

Important things to know about the science behind supplements:

  • The U.S. Food and Drug Administration (FDA) doesn’t regulate collagen supplements. They don’t require the double-blind, placebo-controlled, randomized trials that medications do to be approved. The manufacturers of supplements don’t have to prove that their products are safe or effective before putting them on the market.
  • Many of the studies conducted with supplements are funded by the supplement industry or the study authors have financial ties to the supplement industry.
  • It’s not known if collagen supplements will do what the label promotes.

Finally, keep in mind that ingesting collagen peptides — from foods or supplements — can’t be directed to where you want them to be used. Your body uses these peptides for whatever it needs, be it collagen or protein.

A note from Cleveland Clinic

Collagen plays an important role in providing structure, strength and support throughout your body. The debate around the usefulness of collagen supplements continues. The benefits of collagen may be more hyped in the media than the evidence behind it. More published research studies are needed to show the true health benefits of collagen supplements. In the meantime, you can always help your body make collagen naturally by eating a well-balanced diet full of healthy foods. A well-balanced diet includes chicken, beef, fish, dairy, eggs, beans, leafy greens, other vegetables, whole grains and citrus fruits. To improve damage to the collagen in your skin, don’t smoke, avoid second-hand smoke and wear sunscreen every day.

Last reviewed by a Cleveland Clinic medical professional on 05/23/2022.

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