Collagen is popping up everywhere. This protein has been linked to a wide range of benefits, including more youthful-looking skin, healthier hair, and improved joint health. So it is no wonder that it has grown in popularity over the last couple of years, showing up in our skincare products, beverages, powders, and even in coffee creamers! And there seems to be no sign of its popularity ending anytime soon—in 2020, the global collagen market value surpassed 3.6 billion dollars, and it is expected to reach a valuation of $6.3 billion by 2027.1
So what is actually the deal with collagen? Do you need to consider and supplement? And is there any science to support all of these health claims? We’re diving into everything you need to know —what it is, the health benefits it’s been linked to, and how you can incorporate it into your diet.
Let’s start at the beginning: What is collagen, and why is it needed?
Collagen is the most abundant protein found in the body. To take a step back, let’s look at protein—one of the three macronutrients (along with carbohydrates and fat) needed in larger amounts than micronutrients like vitamins and minerals. It is recommended that healthy adults aim to get anywhere from 10% to 30% of their daily calories from protein.2 This is a big range, so it’s important to know that the amount of protein you eat likely changes every day and depends on the other foods you’ve eaten that day—all completely normal!
Protein Ins and Outs
All proteins are made up of a combination of 20 amino acids. Amino acids act like building blocks to form peptides (short chains of 2–50 amino acids), which bind together into polypeptides (meaning “many peptides”) to form partial or entire protein molecules.
There are nine amino acids that we consider “essential” because the body cannot make them, so we must get them through in our diets—either through food or supplements. The other 11 amino acids are substances that the body can make on its own, so they are deemed “non-essential.”
Collagen protein is made up of 19 amino acids. The one amino acid it lacks is tryptophan, which is one of those nine essential amino acids. Tryptophan is needed by your body to create several different compounds, most notably the sleep-regulating hormone melatonin.3 You may have heard tryptophan mentioned at Thanksgiving since it is present in turkey and often viewed as the reason you need a post-meal nap on the couch.
Types of Collagen
There are actually over a dozen types of collagen found in the body, but the majority are types I, II, and III, which are used within different body structures shown in Table 1.4
Table 1. Major Collagen Types in the Body
|Where It’s Found in the Body
|Skin, tendon, bone, ligaments, dentin (the layer under enamel in teeth), connective tissues
|Cartilage, vitreous humor (a gel-like substance between the retina and lens in the eye)
|Skin, muscle, blood vessels
While we can get collagen from eating certain foods, the body is also able to produce it naturally. But it needs cofactors to do this. You can think of cofactors as helper compounds that are necessary to complete a task in your body. Vitamins and minerals are often cofactors in various processes that occur in your body, and why it is so important to get enough of them. Without sufficient vitamins and minerals, important reactions cannot take place.
Vitamin C is a necessary cofactor for your body to make collagen. Vitamin C also works as an antioxidant, helping to prevent oxidative stress that causes the body’s existing collagen to break down.5
Collagen is an important component of the body’s connective tissues—think structures that link things together, like cartilage and tendons. It is like the “glue” that provides the structure for hair, bones, joints, nails, and skin. It also plays a role in wound healing; the repair of blood vessels, gums, cornea, and scalp; and the development of our organs. The skin is often not recognized as being the largest organ in the body, and two of the most significant structural components of skin are collagen and hyaluronic acid.6
As we age, the body starts to produce less and less, and what we do have breaks down faster. After the age of 40, it’s estimated the body loses 1% of its collagen every year. Since it’s such a big component of our skin, this loss leads to reduced fullness of the skin and wrinkles.7
So it makes sense that supplementing to replete what has been lost would provide anti-aging benefits, making it one of the main reasons why collagen has become increasingly popular.
But do collagen supplements actually work to boost skin health and result in more youthful-looking skin? Is there scientific evidence to support supplements work?
The good news is that some research indicates that taking a collagen supplement may improve skin health and could slow the signs of skin aging.8
A 2019 study of 72 women over the age of 35 found that drinking a collagen supplement beverage “improved skin hydration, elasticity, roughness, and density.” The women also reported that, at the end of the 12-week observation, their skin appearance had significantly improved. 9
While these results are compelling, the research is still rather limited on collagen and skin health. And most studies have been conducted with small groups of people. In addition, there is no data to support that supplementing the diet with collagen can reverse the natural aging process. More research is needed to determine the ideal amount and timing of collagen supplements that best supports skin health.
Another reason why it is difficult to state definitively that collagen improves skin health has to do with the way the body absorbs and digests collagen.
The body cannot absorb collagen in its whole form found in food or supplements—it must be broken down into smaller pieces first. So, once eaten, it is split up during digestion into peptides and amino acids before entering the bloodstream to be used by the body as nutrients. That means that after absorption, the smaller peptides and amino acids can be used to build any proteins the body needs, and they might not be remodeled back into collagen within the body. This complexity is why it is difficult to know if sources from food or supplements actually increase levels in the body.
Other Health Benefits
In addition to being used for skin health, collagen peptide supplementation has also been linked to several other health benefits, including building muscle tone, bone and joint health, and weight loss. It’s important to look at the current scientific literature to understand the scope of these benefits.
Muscle Building Post-Exercise
Taking a protein supplement or eating protein after exercise, particularly weight training or resistance training, is a common practice thought to help boost muscle formation. While it may seem helpful to eat as much protein as possible to build muscle, more is not always better. Research shows that just 20 grams of protein after a workout is enough to help muscles recover sufficiently and stimulate muscle growth.10
The Recommended Daily Allowance (RDA) of protein for healthy adults is 0.8 grams/kilogram.11 For someone who weighs 150 pounds, this is about 55 grams of protein per day. It is important to remember that the RDA is an average daily amount recommended to meet the nutrient requirements for most adults. Protein needs can increase or decrease due to medical conditions, exercise, or lifestyle. Working with a healthcare professional like a dietitian is the best way to determine your individual protein and nutrient needs.
When looking at the science behind collagen peptide supplementation and muscle growth, the findings are mixed. In one study, 57 men were given either 15 grams of collagen peptides or a placebo each day while participating in a 12-week resistance training program. The researchers found that muscle strength had increased significantly in both groups, but the collagen-supplemented group showed increased fat-free mass, which was thought to be due to increases in muscle cell size and possibly connective tissue.12
In another study looking at resistance training and collagen supplementation, 90 women between the ages of 18 and 50 were given either 15 grams of collagen peptides or a placebo over 12 weeks. The findings were similar, with gains in fat-free mass. But the collagen group in this study also had more fat loss, leg strength, and hand-grip strength than the placebo group.13
While these results may appear promising, the differences found between those who supplemented with collagen and those who did not were very small. So you have to weigh the benefits of buying a collagen supplement with the potential for good results.
What’s more, collagen is actually not the best protein source to grab post-workout because it lacks tryptophan, an essential amino acid. This means collagen is not a complete protein source. Complete protein sources like whey or soy, which contain all nine essential amino acids, may be better post-workout choices for muscle-building and recovery.
Bone & Joint Health
Finding ways to improve bone and joint health is also an area of interest. Osteoarthritis has been studied because it occurs when the protective cartilage that provides cushioning between bones wears down over time. A 2019 meta-analysis revealed that collagen supplementation might be effective in improving osteoarthritis symptoms.14
Osteoporosis is a loss of bone mineral density, which causes bones to weaken and be more likely to break. A balanced diet, weight-bearing exercise, and refraining from smoking are several ways you can actively protect your bone health. However, a few risk factors for osteoporosis cannot be modified, like age, gender, and family history.15 Research in postmenopausal women who exhibited age-related osteopenia, an early indicator of osteoporosis, demonstrated that supplementing with collagen peptides increased bone mineral density and reduced bone breakdown.16
Despite these encouraging findings, more research is needed to determine if collagen supplementation is effective for osteoporosis prevention or treatment.
Protein is often a key component of weight loss programs because it provides a feeling of fullness, which suppresses the appetite.
One study had 81 participants who were overweight take either 2,000 mg of skin collagen peptides or a placebo over 12 weeks without making changes to diet or exercise. The authors concluded that those who had taken the collagen supplement had a slightly better reduction in body fat mass and body fat percentage compared to the placebo group.17
Weight loss is a multifaceted process that is different for every individual. There is no single food, supplement, or exercise deemed to be the best solution for everyone. Any diet that contains a variety of fresh fruits, vegetables, whole grains, lean meat, fish, beans, nuts, and seeds can help support overall health.
The research on collagen supplements and health is promising, but the jury is still out. It is hard to link any significant health benefits to collagen specifically, and since the body must break it down to use it, there is an additional layer to keep in mind when reviewing new research about collagen supplementation.
Do you have to get collagen from a supplement, or are there food sources?
Yes, we can get collagen through a variety of foods. One of the most common food sources is bone broth. By simmering bones over many hours, nutrients contained within the bones, joints, and tendons are released, including collagen. Like humans, animals also carry an abundance of collagen in muscle and connective tissue, making most animal meat products good sources of collagen, while organ meats (like liver, for example) are not.
When it comes to finding a supplement, there are several different types available: collagen peptides, beef (bovine) collagen, marine collagen, and collagen whey.
Collagen peptides are generally the most popular since they mix well in both cold and hot beverages, which makes them easy to add into smoothies or coffee. Beef collagen is commonly used to make protein-rich gummies or Jell-O.
The difference between beef and marine collagen is the type of collagen molecules that comprise each. Beef collagen has higher levels of types I and III, while marine has more of types I and II (see Table 1). Because type II is mostly concentrated in cartilage, while type III is found more broadly in skin, muscle, and blood vessels, bovine collagen is often preferred over marine for its span of health benefits. Dietary preferences like veganism make marine collagen a better option for some people.18
It is important to know that the Food and Drug Administration (FDA) does not regulate collagen peptide supplements. And while generally safe to take, many healthcare professionals agree that collagen supplements may not be worth the money. Since they don’t have to be proven safe before being placed on the market, you have no way of knowing what is actually contained in that supplement and how much of it. 19 Supplements may have inconsistent amounts of collagen present or other ingredients that could interact with medications you take.
Look for a supplement that lists collagen as the first ingredient and, ideally, one that contains collagen peptides since the smaller protein pieces are easier for your body to absorb. It is always a good idea to have a discussion with your doctor before taking any new dietary supplements.