What Is Collagen, and What Is It Good For?

What is collagen and why is it important?

Collagen is a type of protein. In fact, it’s the most abundant structural protein in animals. A structural protein is one that makes up the structure or framework of your cells and tissues ( 1 ).

There are 28 known types of collagen, with type I collagen accounting for 90% of the collagen in the human body ( 2 ).

Collagen is composed mainly of the amino acids glycine, proline, and hydroxyproline. These amino acids form three strands, which make up the triple-helix structure characteristic of collagen ( 3 ).

Collagen is found in connective tissue, skin, tendons, bones, and cartilage. It provides structural support to tissues and plays important roles in cellular processes, including ( 3 , 4 , 5 , 6 ):

• tissue repair
• immune response
• cellular communication
• cellular migration, a process necessary for tissue maintenance

Connective tissue cells called fibroblasts produce and maintain collagen. As people grow older, their collagen becomes fragmented, fibroblast function becomes impaired, and collagen production slows ( 3 , 7 ).

These changes, along with the loss of another key structural protein called elastin, lead to signs of aging such as sagging skin and wrinkles.

Collagen uses

Your body naturally produces collagen, and you can consume it through dietary sources such as chicken skin and fish skin as well as collagen supplements.

Oral and topical collagen products like supplements and face creams are popular for treating signs of aging such as wrinkles, loss of skin hydration, and joint pain.

You can buy collagen in powder, capsule, and liquid form.

You can take it as a supplement or add it to beverages — both hot and cold — and foods such asoatmeal, yogurt, and energy balls.

Healthcare professionals also use collagen and collagen-based materials in the medical field, including in treating wounds, burns, and diabetic ulcers ( 8 ).

Additionally, cosmetics companies use collagen in products like moisturizers and serums because of its moisturizing and humectant properties ( 9 ).

Summary

Your body makes collagen naturally. Collagen is found in connective tissue, skin, tendon, bone, and cartilage and has many functions. It’s also present in some foods, and you can take it as a supplement.

What causes collagen loss?

As you age, your collagen production naturally declines. Additionally, collagen becomes fragmented and more loosely distributed ( 10 ).

These changes lead to the characteristic signs of aging, such as wrinkles and dry, sagging skin. The integrity of the collagen found in the skeletal system decreases with age as well, leading to reductions in bone strength ( 11 ).

While collagen loss and damage as you age are inevitable, certain dietary and lifestyle factors can accelerate this process.

For example,smoking cigarettesis known to degrade collagen and cause skin aging, wrinkles, and loss of elasticity ( 12 , 13 ).

Excessive drinkinghas also been shown to accelerate skin aging by reducing collagen production and damaging skin repair mechanisms ( 13 ).

Additionally, following a diet high in added sugar and ultra-processed foods can lead topremature aging导致这一过程被称为糖化,which reduces collagen turnover and interferes with collagen’s ability to interact with surrounding cells and proteins ( 14 ).

Excessive sun exposure degrades collagen production as well, so wearing sunscreen and avoiding excessive sun exposure can help prevent signs of premature skin aging ( 15 ).

Summary

Age-related collagen loss is unavoidable, but dietary and lifestyle factors such as smoking and excessive alcohol intake can speed up this process.

Best food sources of collagen

Collagen is found in all animals, and it’s concentrated in some parts of an animal, such as skin and joints.

Here are few examples of collagen-rich foods ( 16 ):

• bones, skin, and ligaments of animals, such as chicken skin and pig knuckle
• certain types of seafood, such as fish skin and jellyfish
• products made from animal parts such as bones and ligaments, includingbone broth

Because your body naturally produces collagen from amino acids, you can support collagen production by ensuring that you’re eatingadequate amounts of proteinfrom foods like poultry, fish, beans, and eggs.

In addition to amino acids, your body needs other dietary components for collagen production and maintenance.

For example, vitamin C is necessary for collagen synthesis, so having low or deficient levels of vitamin C can lead to impaired collagen production ( 17 ).

Therefore, consuming plenty ofvitamin C-rich foodscan help support healthy collagen production. For example, try citrus fruits, peppers, greens, and berries.

What’s more, consuming a diet high in beneficial plant compounds could also help improve skin health by reducing inflammation and protecting against collagen degradation ( 18 ).

Summary

Certain foods, such as animal skin and ligaments, are rich in collagen. A collagen-supportive diet should include protein-rich foods as well as fruits and vegetables, which are rich in vitamin C and other antioxidant and anti-inflammatory compounds.

Are there benefits to taking collagen supplements?

Studies have shown that taking collagen supplements may offer a few benefits.

Potential skin benefits

One of the most popular uses of collagen supplements is to support skin health. Research suggests that taking collagen supplements may improve certain aspects of skin health and appearance.

A review of 19 studies that included 1,125 participants (95% women) between the ages of 20 and 70 found that taking hydrolyzed collagen improved skin hydration, elasticity, and wrinkles compared with placebo treatments ( 19 ).

Hydrolyzed collagen is a common type of collagen used in supplements that is created using a process called hydrolysis. This process breaks down the protein into smaller pieces, making it easier for the body to absorb ( 20 ).

A number of studies have shown that taking collagen supplements may improve skin hydration andelasticityand reduce the appearance of wrinkles.

However, keep in mind that many of these studies were funded by companies that manufacture collagen products, which could have influenced the study results ( 21 , 22 ).

The doses of collagen shown to be effective for improving skin health in research studies vary, though most studies have used 2.5–15 grams per day for 8 weeks or longer ( 23 , 24 ).

Potential benefits for bones

In addition to improving some aspects of skin health and appearance, collagen supplements may offer a few other benefits.

One study looked at the effects of taking collagen supplements in 102 women inpostmenopausewho had reduced bone mineral density (BMD).

Those who took 5 grams of collagen peptides per day for 1 year had significant increases in BMD in their spine and femur (a bone in the lower leg) compared with participants who took a placebo ( 25 ).

A follow-up study in 31 of these women found that taking 5 grams of collagen daily for a total of 4 years was associated with a progressive increase in BMD.

The researchers found that participants’ BMD increased by 5.79–8.16% in the spine and by 1.23–4.21% in the femur during the follow-up period ( 26 ).

These findings suggest that taking collagen supplements long-term may help increase bone mineral density in people in postmenopause, who are at a greater risk of developingosteopeniaand osteoporosis.

What’s more, one review article concluded that taking oral collagen supplements reduced participants’ symptoms related to osteoarthritis, including stiffness ( 27 ).

Collagen supplements may provide other health benefits as well, such as improving body composition in certain populations when combined withresistance training( 28 ).

It’s important to note that studies observed these beneficial effects of taking collagen mainly in older women with low bone mineral density.

因此,胶原蛋白补充剂可能没有ame effects in other populations, such as men, those who are younger, or those who don’t have low bone mineral density.

Do collagen supplements have side effects?

Collagen supplements have a good safety profile and are not associated with adverse side effects.

However, manufacturers often combine collagen with other ingredients in supplements. Certain ingredients could pose health risks, such as herbs and high levels of vitamins in supplements formulated to support the health of the skin, nails, and hair ( 29 ).

For example, dietary supplement ingredients such as herbal extracts may interact with commonly prescribed medications, and some aren’t safe for people who are pregnant or breastfeeding.

What’s more, some supplements that contain collagen may also contain megadoses of nutrients likebiotin, which could interfere with laboratory tests for heart and thyroid function.

This and other vitamins and minerals could cause health issues if you take them in high doses for a long time ( 29 ).

So, while supplements that contain only collagen are unlikely to cause any side effects, it’s important to read labels and understand the potential risks of supplements containing collagen combined with other ingredients.

If you’re taking other medications or you’re pregnant or breastfeeding, make sure to speak with a healthcare professional before you start taking supplements.

Collagen supplements vs. protein

It’s important to note that you don’t need to eat collagen or take collagen supplements to support your body’s collagen levels or bone health.

In fact, you can help your body make collagen and maintain healthy collagen levels and bone tissue by simply including enough high quality protein, vitamin D, calcium, vitamin C, and zinc in your diet (30, 31 , 32 ).

吃均衡的饮食有更多的蛋白质especially helpful for maintaining muscle tissue and bone as you get older. Experts recommend consuming more than 0.36 grams of protein per pound (0.8 grams per kg) of your body weight for this purpose (30).

To support this, combine this protein-rich diet with physical activity, especially resistance training and weight bearing exercise (30).

Summary

Collagen supplements may help promote the health of the skin and skeletal system and may help improve symptoms related to osteoarthritis. They’re considered safe on their own but may contain other ingredients that aren’t appropriate for everyone.

How to prevent collagen loss

It’s impossible to prevent all age-related collagen loss, but it is possible to slow down the process.

As mentioned above, diet and other lifestyle factors can significantly affect your body’s collagen production.

Smoking cigarettes and drinking excessive amounts of alcohol negatively affect collagen production, as does following a diet high in ultra-processed foods andadded sugar( 12 , 13 , 14 ).

On the other hand, leading a healthy lifestyle by following a nutrient-dense diet and avoiding smoking and heavy alcohol use may help delay age-associated changes in collagen and reduce signs of aging such as wrinkles.

Avoiding or reducing your intake of certain foods and beverages while increasing your consumption of others may help support collagen maintenance and overall skin health.

For example, a diet low in compounds calledadvanced glycation end products (AGEs)may help promote skin health. AGEs are toxins that accumulate in the skin. They can cause collagen to stiffen and can inactivate proteins responsible for collagen repair ( 33 ).

Foods highest in AGEs include processed meat products like hot dogs and bacon, fried foods like french fries and fried chicken, and roasted and grilled meats, according to newer and older research ( 33 , 34 ).

Additionally, following a diet high in high quality protein andplant foodssuch as fruits and vegetables, which contain collagen-supportive and protective nutrients, may also help protect collagen stores and prevent collagen damage and loss ( 33 ).

Summary

Maintaining a healthy lifestyle by avoiding cigarette smoking and excessive alcohol consumption and following a diet rich in fruits, vegetables, and other nutritious foods can help protect against collagen loss and damage.

The bottom line

Collagen is a protein found in connective tissue, skin, tendon, bone, and cartilage.

It provides structural support to tissues and is also involved in essential bodily processes, including tissue repair and signaling between cells.

Your body makes collagen naturally, but you can also consume it through collagen supplements and certain foods, which may benefit the health of your skin, your bones, and more.

研究表明,服用胶原蛋白似乎是一部分icularly helpful for certain purposes and populations, including for increasing bone mineral density (BMD) in people in postmenopause who have low BMD.

Consuming enough protein, vitamin C, vitamin D, and zinc in a balanced diet is a healthy and less expensive alternative to supplements. By combining this with regular exercise, you can help minimize collagen and bone loss as you age.

Even though age-related collagen loss is unavoidable, leading a healthy lifestyle can help protect against collagen loss, delay signs of aging, and promote overall health.