Medically reviewed by Patrick Carroll, MD
Written by Our Editorial Team
Last updated 11/18/2019
If you keep up to date on the latest health and wellbeing trends, you’ve no doubt seen the words “collagen peptides” mentioned in blog posts, guides and top 10 lists all over the place.
For most of us, collagen is an ingredient in skincare products such as anti-aging creams, balms and moisturizers. However, collagen is actually much more than just a skincare ingredient — it’s one of the most important proteins for your body’s connective tissue.
Your body naturally produces collagen. However, as you age, the amount of collagen produced by your body declines. Collagen peptide supplements make it easier to maintain steady collagen levels, potentially contributing to healthier skin, bones and other tissue.
Below, we’ve explained what collagen peptides are and what some of the evidence out there says about the role they can play in keeping your skin and body fit and healthy.
We’ll go through some potential advantages offered by collagen peptides that are still undergoing research, as well as break down some of the hype out there that isn’t currently supported by research.
Collagen peptides are a hydrolyzed form of collagen that you can add to smoothies, coffee and other food and drinks. Most collagen peptides come in powder form, although some are sold as capsules and liquids.
It’s hypothesized that using a collagen peptide supplement potentially helps make up for the natural decline in collagen that occurs with age.
Before we can get into the specifics of collagen peptides, it’s important to explain what collagen is and the numerous ways in which your body uses it to grow and maintain healthy skin, bones, joints, hair and nails.
Collagen is an essential structural protein that’s the main component of your body’s connective tissue.
In fact, it accounts for one third of total protein and three quarters of the dry weight of your skin.
To a certain extent, you can think of it as a type of connective superglue that holds all of the other components that make up your body together.
Most people associate collagen with things like soft, elastic skin.
While this is a part of the role that collagen plays in your body, collagen is responsible for much more than just keeping your skin smooth.
Aside from water and fat, your body is made up of a lot of protein. Your muscles, bones, organs, hair, skin and nails all consist primarily of different proteins.
There are numerous different proteins in your body, all of which play important roles in helping you function. Actin and myosin, for example, are abundant in muscle cells and are responsible for processes such as muscular contraction.
Hemoglobin, on the other hand, is a vital protein that’s found in your blood. It’s responsible for carrying oxygen in your blood from the lungs to the other tissues of your body.
In short, each and every protein in your body plays a different — but important — role in keeping you alive, healthy, fit and capable of doing the things you need to do.
Of the numerous proteins that are present in your body, collagen is the most abundant.
To put it another way, if you were to view your body’s proteins as a pie chart, the collagen would make up around a third of the pie, with the various other proteins in your body each accounting for a smaller slice.
Although most people think of collagen as just collagen, there are actually numerous different types of collagen in the body.
Currently, we’ve identified twenty-eight. Of these, collagen types I, II and III are the most common. In fact, type I alone accounts for more than 90 percent of the body’s total collagen content.
Collagen’s role is to provide structural support to your body’s connective tissues, such as your skin, tendons, bones, ligaments and internal organs.
Like we mentioned earlier, it can help to think of collagen as your body’s superglue — a protein that helps hold the other key components in healthy tissue together.
For example, collagen is an extremely common protein in your skin. In the skin, collagen plays an important role in stimulating the production of new skin cells, helping to keep your skin soft, smooth and elastic.
This process keeps your skin youthful and contributes to preventing the development of age-related skin issues such as wrinkles, crow's feet and jowls.
Collagen also plays a role in the healthy function of your internal organs. For example, collagen is part of the base structure of the kidney filters.
It’s also present in vascular tissue, the liver and lungs, your eyes, your gut and in the cartilage that covers, protects and connects your bones.
Simply put, collagen is an essential building block for a huge percentage of your body’s skin and internal tissue. Without it, just about every part of your body — from your skin and hair to your vital organs — can’t function.
Your body naturally produces its own collagen. Collagen is secreted by a range of different cells, with the connective tissue cells typically producing the most.
Collagen production is generally at its highest when you’re in your teens and early twenties. As you get older, your body’s natural production of collagen begins to slow down.
In a laboratory study published in The American Journal of Pathology in 2006, researchers looked at the skin biopsies from people aged 18 to 29 and compared it to skin skin biopsies from people 80 or older.
Results indicated that older people had a 75 percent lower rate of collagen synthesis compared to people aged 18 to twenty-nine.
Of course, collagen production doesn’t suddenly decrease by 75 percent once you hit eighty. Instead, your body’s ability to produce new collagen gradually decreases at a rate of about one percent every year, starting from the age of twenty.
The result of this gradual decline in collagen production is thinner, less elastic skin and a more pronounced appearance of wrinkles, smile lines, jowls and other aesthetic skin issues related to aging.
There is speculation that including more collagen in your diet can help slow down some of the age-related effects resulting from this gradual decline in collagen production.
Collagen-rich foods, or foods rich in amino acids that may contribute to its production, include foods like fish, bone broth, egg whites, garlic, beans and certain berries.
However, making radical changes to your diet just to get more collagen isn’t always an easy thing to do.
The amount of collagen in certain foods can also vary — while the “meat” of fish isn’t very rich in collagen, less appetizing parts like the head and skin are.
That’s why we have collagen peptides. Collagen peptides are hydrolyzed, bioavailable collagen protein that you can take to supplement your body’s natural production of collagen without making major changes to your diet.
Collagen peptides have grown tremendously in popularity over the last few years, largely as a result of bloggers and wellness enthusiasts touting the benefits of collagen.
According to data from Google Trends, the number of people searching online for information about collagen has more than tripled over the past five years. There’s also a growing level of interest in collagen-rich foods such as bone broth and certain meats.
Like many other health trends, part of the reason for collagen’s sudden increase in interest is exposure. More than ever, a growing number of people are aware of the potential benefits of collagen, both from general health and anti-aging perspectives.
Another reason is the convenience factor. Collagen peptides are just as convenient and easy to use as any other powder-based supplement.
For instance, you can add them to a morning smoothie, mix them into your cup of coffee or take them after a workout like you would a protein shake.
Research into the potential benefits of collagen peptides is still ongoing, meaning that while there’s currently evidence that collagen might have certain benefits, additional support for the benefits of collagen peptides is continuously being added to the body of research out there.
We’ve listed some of the potential benefits that have been studied to date, along with the current scientific research behind each one.
Arguably the biggest potential benefit of collagen supplements is that they may improve the appearance of your skin. Research suggests that using a collagen supplement might help to slow down certain signs of aging, such as the age-related decline in collagen production.
As noted above, collagen is by far the most abundant protein in the skin, accounting for about 75 percent of your skin’s dry weight.
As you age, it’s normal for collagen levels to gradually decline, resulting in lower levels of elasticity and visible wrinkling that’re common in older people’s skin.
Most of the decline in collagen synthesis is a natural result of the aging process. However, some factors, such as photodamage from sun exposure, may also affect your body’s ability to produce certain types of collagen.
Studies of collagen show that regular use of collagen peptide supplements can potentially reverse some of this damage, contributing to smoother, more elastic and less wrinkled skin.
In a 2014 study published in Skin Pharmacology and Physiology, researchers analyzed the skin elasticity, moisture, roughness and water loss of 69 women aged between 35 and 55 over a four-week period.
The researchers found that the women who used 2.5g or 5g of a collagen peptide supplement had a statistically significant increase in skin elasticity after four weeks.
The collagen peptides also had a positive influence on the women’s levels of skin moisture and skin evaporation.
Another study from 2018 found that daily use of collagen peptides improved skin hydration and reduced wrinkling over a period of 12 weeks.
Finally, a study from 2015 found that oral supplementation using collagen peptides resulted in increased skin hydration and higher levels of collagen density in the dermis (the layer of skin below the outermost epidermis).
In short, using a collagen peptide supplement may increase the collagen content of your skin, helping it stay soft, elastic and healthy while reducing your risk of developing wrinkles.
Collagen is a protein, meaning that collagen peptides can contribute towards your daily protein intake. Research suggests that taking collagen peptides supplies your body with a good source of protein.
As the International Society of Sports Nutrition states, “An acute exercise stimulus, particularly resistance exercise, and protein ingestion both stimulate muscle protein synthesis (MPS) and are synergistic when protein consumption occurs before or after resistance exercise.”
As such, if you like to work out, a collagen supplement could help you get better results.
A study published by the British Journal of Nutrition in 2015 evaluated the use of collagen peptides in 53 men 65 and older with age-related muscle loss in combination with a resistance training regimen.
Study participants were given either 15g of collagen peptides or placebo to take within an hour after exercising.
After three months, the men in the collagen peptides group had gained more strength and muscle mass than the men who followed the same exercise program without using collagen peptides.
Of course, it’s not only older men benefitting from collagen supplementation. In a recent study of 25 young men in their mid-20s, study participants were given 15g of collagen peptides or placebo every day for 12 weeks to consume within an hour after completing a resistance training session.
Across the board, by the end of the study, fat-free mass, body mass and muscle strength all increased more in the collagen peptide group as compared to the placebo group.
If you’re physically active, adding collagen peptides to your daily routine can make it easier to reach your target protein intake.
This could contribute to better muscle and strength gains over the long term, as well as improved recovery after you exercise.
With this said, it’s worth noting that collagen isn’t a perfect protein for muscle protein synthesis and sports performance.
Unlike whey, casein and the protein found in meat, collagen is light in leucine — an essential amino acid for building and repairing muscle tissue.
This means that while collagen peptides can help you build and maintain muscle, it’s better not to rely on them completely. Instead, try adding collagen to a balanced diet that’s rich in different sources of protein.
While there isn’t any evidence that collagen burns fat by itself, there evidence to suggest that eating collagen supplements as a part of a meal may make you feel full longer, which in turn could help you stick to a diet.
In a study of 24 healthy young adults, a breakfast containing gelatin resulted in a reduced appetite at lunch three hours later compared to a breakfast containing casein, soy and whey proteins.
However, the breakfast used for this study also contained other protein sources, making it difficult to draw a clear conclusion.
In short, while collagen isn’t a fat burning substance, there’s some evidence that it can help to suppress your appetite and keep you full longer.
Additionally, there are other studies that show collagen may promote joint health and support muscle recovery after exercise.
One 24-week study of athletes — a group at particularly high risk of joint and muscle pain — who either took 10g of collagen hydrolysate or placebo, found that athletes who took collagen had significant improvement in joint pain.
Another study also tested collagen’s potential effects on muscle recovery and found that, in a small group of men who took 20g of collagen peptides daily, athletes who consumed collagen experienced moderate muscle recovery and improved muscle soreness in 48 hours post-exercise.
There is some evidence that collagen peptides may contribute to healthier nails.
In a study published in the Journal of Cosmetic Dermatology in 2017, daily use of bioactive collagen peptides resulted in a 12 percent increase in nail growth rate, fewer cases of brittle nails and a general improvement in nail appearance.
Search online for information about collagen and there’s a good chance you’ll stumble onto a guide or blog post recommending it as a treatment for everything from acne to broken bones, male pattern baldness and even heart disease.
While these benefits can look appealing at first, not all of the claims made about collagen are backed up by evidence. We’ve looked at some of these claims below.
While using a collagen supplement has been shown to improve the overall appearance of your skin, there’s no evidence that collagen treats or prevents acne.
Acne is caused by a buildup of sebum and dead skin cells. When these build up inside a pore, it can cause a pimple to develop.
Just like acne, there’s no scientific evidence that collagen prevents or helps to manage eczema symptoms. There’s also no scientific evidence to suggest that collagen supplements can treat or cure psoriasis and other immune-related skin conditions.
Collagen is often recommended as a natural treatment for leaky gut syndrome — a hypothetical medical condition unrecognized by mainstream medicine that’s claimed to lead to a wide range of common, often severe health conditions.
Although increased intestinal permeability is a recognized medical condition, many of the claims made about leaky gut aren’t supported by scientific evidence. These include the claim that using collagen supplements can treat, repair or heal a leaky gut.
Contrary to certain claims you might see online, there’s no evidence that collagen directly burns fat. Collagen is not a stimulant and has not been proven to increase metabolic rate or affect the amount of energy you burn over the course of a day.
As we covered above, there is some evidence that incorporating collagen peptides into a meal can make you feel full for longer, which could make it easier to stick to a weight loss diet. However, taking collagen on its own will not cause your body to burn fat.
This is another common claim that can be found circling the internet. While collagen is rich in glycine, an amino acid that’s linked to a range of potential sleep benefits, there isn’t any evidence that taking collagen peptides before bed will help you fall or stay asleep.
Collagen is an essential protein produced by the body. As we age, our bodies produce less and less of it. Many foods contain collagen, but there are also supplements of various forms containing collagen peptides that can be added to your diet.
Since collagen peptides come in powder form (as well as in liquids, capsules and even gummies), it’s easy to add them to smoothies, your morning cup of coffee or even a post-workout protein shake.
Research is ongoing, but there is solid evidence that increasing the amount of collagen you — either through collagen-rich foods or collagen supplements — could provide a number of benefits.