Collagen is the most abundant protein in the human body. It's a critical structural element in your hair, skin, bones, connective tissues, and nails. Because of this, people often feel like getting more collagen, either as a topical treatment or as a supplement, can help enhance those aspects of the body. This isn't quite true, though, so let's discuss what's really happening and how it can affect your hair.
Collagen in Hair
Collagen is abundant throughout the body, including the hair, but it's not actually quite as prominent in hair as you might think. Rather than being part of your hair itself, it's relevant for the hair follicle, the pore-like hole in your skin that grows the hair.
Collagen is found in the outer shaft of the hair, but that collagen isn't "alive" in the same way collagen in your skin and bones is alive. Since your hair doesn't heal from damage, it relies on treatments like oils, moisturizers, and other topical applications to stay clean and healthy-looking. Instead, collagen is primarily used in the growth part of your hair, centralized in the hair follicle.
Before we can talk about how collagen affects the hair, we need to discuss the hair growth cycle.
Hair Growth Cycles
Contrary to popular belief, your hair isn't just constantly growing at a fixed rate. Rather, it grows in a cycle. This cycle has three phases.
The first phase is the anagen phase. The anagen phase is the active, growing phase of your hair. Your hair follicles grow and divide at a rapid rate, staying active and growing for quite a while, anywhere from two to seven years. During this time, your hair grows around 1 centimeter per month, depending on your personal genetics.
Once the anagen phase starts to end, your hair follicles enter the catagen stage. The catagen stage is a transitional stage and lasts around two or three weeks. This is sort of like a "shutdown process" for your hair. Growth stops, and the hair sheath shrinks and attaches to the root of the hair, forming what is called a "club hair." This hair no longer grows, and there's nothing you can do to stimulate it into growing again.
The telogen stage is the third stage of the hair cycle and typically lasts around 100 days. This is the result of the catagen stage's cessation of growth. The hair follicle is dormant and inactive. The hair, cut off from its growth line, eventually falls out. If you've ever wondered why you shed hair, this is why; the hairs in the telogen phase simply fall out.
Don't worry; this cessation is not permanent. After the dormancy period of the telogen phase, the hair follicle returns to life and new hair starts to grow in that follicle. If the old hair has been shed – which it usually has – it's free to grow. If the hair has not yet been shed, the new hair will push the old hair out and it will shed then.
Your hair is not uniform in its progression through this cycle. At any given time, around 3% of your hair is progressing through the catagen phase, and another 6-8% is in the telogen phase, while the rest is still actively growing. Given that the average person has around 100,000 hairs on the scalp, that's still plenty of hair for most people. Of course, the hair cycle applies to hair all over the body as well, though that hair doesn't tend to grow as long.
How Collagen Affects the Hair Cycle
Collagen may impact the hair cycle, though the impact is not currently well-studied. Here's what we know: collagen is thick and strong during the anagen phase of hair growth. When the follicle reaches the catagen stage, collagen drops away. It's likely, though not confirmed, that the presence of collagen helps the hair grow thicker and stronger, though not necessarily longer or faster.
We know that collagen is present in hair growth, but we don't know what it does. We also don't know whether or not adding more collagen will strengthen hair, make it grow faster, or otherwise impact the hair growth cycle at all. See, there's one tricky thing about collagen, and that's how the body uses it.
How the Body Uses Collagen
Collagen is a huge molecule, and it is not absorbed through the skin. Most collagen skin treatments don't do anything. Collagen in a skin cream? Most of it is underwhelming. This includes scalp treatments; collagen applied to the scalp won't do much, if anything.
There are two ways collagen can get "under your skin" so to speak and have an impact on the body. The first is as an injected filler.
A collagen filler, injected subcutaneously, serves to fill out low spots and wrinkles in your skin. This, however, isn't really your body using the collagen, so much as just packing material beneath the skin. Collagen is used because it's a safe protein for the body to absorb, not because it has any special utility.
The other way is to eat collagen. Again, though, there's a bit of a misconception here about how the body actually uses collagen.
Many people seem to think that your body uses collagen and you can eat collagen, so when you eat collagen your body just identifies it and ferries it to the appropriate locations to be used. That's not actually how it works.
Instead, your body needs to break down and digest the collagen protein, and use its constituent parts – the amino acids – throughout the body. Your process of digestion breaks down the collagen into little bits, then stores those bits throughout the body in pools to draw on as necessary.
Incidentally, collagen peptides will often come up in this part of the discussion. Since your body needs to break down collagen before it can be used, why not break down the collagen before eating it, to make it even easier for your body to use? That's what collagen peptides are. The single long collagen molecules are broken down into peptides, which your body finds easier to then further break down into amino acids, vitamins, and minerals. Collagen peptides are just a more direct way of getting collagen in your diet than getting in whole through bone broth.
In order to actually use those building blocks, you also need a key ingredient to put them back together into collagen. That ingredient is Vitamin C. Without vitamin C, your body can't produce collagen. You also need some minerals, including iron, zinc, and copper, in order to produce collagen.
Collagen is destroyed regularly in the body. It is used and consumed throughout the body to repair microdamage in the skin, bones, and connective tissues. It is consumed as hair grows. It is also destroyed by outside factors like smoking, UV rays, and stress, which produces cortisol, which breaks down collagen. Additionally, as you age, your body produces less collagen naturally. Increasing your collagen intake can only offset this so much because it's the slowdown of a bodily process, not a lack of ingredients that causes the problem.
None of this is meant to say that collagen doesn't work. It's just slightly more complicated than many people think, and you can get the benefits of collagen by eating foods with the building blocks of collagen rather than just the collagen directly, but both is of course even better.
How Collagen Supports Hair Growth
So how does collagen support hair growth? The answer is simple: nutrition. Healthy hair needs proper nutrition to grow, and that includes both the building blocks for collagen and the building blocks for the hair itself. This includes nutrients like biotin, vitamins like A, D, and E, and of course the amino acids that form collagen.
There's no real research done as to how collagen intake impacts hair growth, hair strength, hair health, or other factors. There have been a few studies, but those studies tend to be small, poorly formulated, and often sponsored by the companies selling collagen in the first place. In other words, they aren't very statistically significant. No large, long-term study has been performed as of yet.
That's not to say that collagen doesn't benefit the hair. It just means that any benefits have not yet been tested and proven by science. Anecdotally, many people who take collagen supplements report noticing that their hair grows faster and longer. This might indicate that collagen fuels hair growth, allowing it to grow faster, and keeps the anagen stage going longer, to allow for longer hair growth and less shedding.
Can You Get Too Much Collagen?
So if collagen may help hair, is it possible that too much collagen can have the opposite impact? Thankfully, probably not. Eating too much of a collagen supplement is unlikely to do any damage. Your body will either not break down some of it and it will pass through you, or it will break it down and use the excess building blocks for other purposes throughout the body.
There is one medical condition related to excess collagen, called Scleroderma. Scleroderma is an autoimmune condition that causes your body to produce too much collagen. When this happens, it makes your skin act strangely, typically by thickening and hardening. Localized scleroderma affects the skin, but a worse condition, systemic scleroderma, has the same impact on internal organs where collagen is in heavy use, including the heart, lungs, and kidneys.
While the exact cause of scleroderma – and indeed most autoimmune diseases in general – is unknown, it's not something you can trigger by eating too much collagen. You either have it or you don't. That said, if you have scleroderma, you should probably avoid taking extra collagen supplements.
Problems with Hair Loss
Hair loss can be caused by a variety of different problems, and some of those problems may benefit from collagen supplements, while others won't.
Some hair loss is caused by some form of malnutrition. An unbalanced diet or a diet that lacks certain proteins and minerals can have widespread issues throughout the body. For example, if you aren't eating enough vitamin C, your body would have a hard time putting together all the collagen it wants. Eating more vitamin C can help solve that issue.
Other hair loss can be caused by stressful events. Because of how long the hair cycle is, though, this means you'll often have a stressful event, and find yourself losing a lot of hair a month or two later. This is because the stressful event triggers the telogen stage of the hair cycle early, but it takes some time for the hair to transition through the catagen stage and into the "hair loss" stage. This hair loss is temporary unless you keep experiencing stressful events, at least.
It's possible that the stress causes high cortisol (the stress hormone) levels in the body, and that cortisol damages the collagen in the hair follicles, leading to the catagen stage early. That's just a theory, but if it's the case, enhancing the collagen you take in could help counteract the effects of stress, particularly on your hair. It won't inherently reduce stress just by taking the supplement, but if you can combine it with relaxation, meditation, exercise, and healthy eating, it can benefit you across the board.
Let Us Know Your Experiences
Many of you are fans of our collagen supplements, so we're curious: what have you experienced while taking them? Specifically, think about your hair.
If you have hair loss, has collagen slowed it down? Has it stopped progressing entirely? Do you find that your hair grows longer, faster, or thicker? We'd like to hear your stories, so leave us a comment and let us know.