Does Collagen Thicken Hair?

Posted July 2024

Does Collagen Thicken Hair? - The Collagen Co.

“Collagen thickens hair.” 

A standard, unsurprising, knee-jerk reaction to this statement is a boatload of skepticism. Hair is made up of keratin, a protein with a completely different amino acid profile — from number to sequence — from collagen, the main structural protein of connective tissues. 

So, how can it be that collagen thickens hair? But we’re getting ahead of ourselves. It wouldn’t make sense to talk about the “how” bit without first addressing this core question:

Does collagen thicken hair?

It does. 

Before we share the supporting evidence, though, let’s all get on the same page about what “thicker hair” means. It can mean increased hair density. I.e., more hair per square inch of scalp. And it could also mean thicker hair strands. 

Now, it's time for the proof. Several clinical trials involving human participants (so no worries about the generalizability of findings) show that collagen benefits hair thickness on both fronts:

  • 2024 study published in Clinical, Cosmetic, and Investigational Dermatology: Collagen supplementation (more specifically, a combination of hydrolyzed collagen peptides with hyaluronic acid and biotin) led to a significant reduction in hair fall compared to placebo. 
  • 2012 study published in the Journal of Clinical and Aesthetic Dermatology: Significantly more participants assigned to daily marine collagen complex supplementation reported perceived improvements in overall hair volume, scalp coverage, and thickness of hair body* than those in the placebo group. 
  • How does collagen thicken hair? 

    Some crucial background knowledge on hair growth you must know.

    What to know about hair growth

    Hair structure

    Each hair has a hair shaft and a hair root. 

    The shaft is the visible part of your hair that sticks out, while the hair root is embedded in the scalp, extending down to the deeper layers of the skin. At the base of the hair, the hair root widens to a round hair bulb — this is the region of the follicle that actively produces hair.

    Hair growth

    New keratinized cells are constantly forming in the hair bulb. These cells “clump” together and harden. 

    Because new hardened keratinized cells continue attaching to the hair “from below”, it is gradually pushed up out of the skin, extending the hair strand’s length.

    It’s a cycle

    There are 3 phases to the hair growth cycle. 

    The anagen phase is where new hair cells continue to grow in the hair bulb. At any point in time, about 90% of your hair is in this active growth phase. 

    At the end of the anagen phase, the hair root separates from the papilla, which supplies it with blood and nutrients. 

    A transitional phase called the catagen phase starts. This lasts anywhere between 2 to 4 weeks.

    The complete separation of the hair root from the papilla kickstarts the final phase, known as the telogen phase, where the hair falls out. 

    New hair cells then multiply at the base of the “empty” hair follicle — restarting the anagen, catagen, and telogen cycle all over again. 

    How collagen thickens hair

    Alright, now that we’ve gotten all that out of the way, here are the 3 leading theories (as put forth by researchers) on how collagen thickens hair:

  • Provides building blocks for hair growth: While collagen and keratin are structurally different, they’re both made up of the same basic building blocks. Amino acids. This means the hair bulb can and will likely use the collagen-peptides-derived amino acids to form new keratinized cells that’ll harden and continue “pushing up” to eventually become thick, healthy hair strands.
  • Promote scalp thickness: Remember what the hair root is embedded in? Yep, it’s the scalp. By stimulating collagen-producing fibroblast activity and counteracting oxidative damage from UV exposure, collagen peptides encourage a healthy scalp, providing a stable anchorage for hair to grow (and continue growing). 
  • Prevent premature hair root separation: As mentioned earlier, generally, 90% of your hair is in the anagen phase. However, the actual percentage may be lower. This means more of your hair is in the catagen and telogen phases, resulting in excessive hair shedding and thinning. Thankfully, research shows collagen peptides may prevent your hair from prematurely exiting the anagen (“growth”) phase, supporting healthy, thick hair growth. 
  • Complement collagen with other hair-boosting actives

    It’s clear that collagen thickens hair. 

    But if you scroll back to the section where we covered the 2024 study, you’ll notice that the researchers used a collagen supplement containing a mix of collagen peptides, hyaluronic acid, and biotin. 

    Why? Answer: because these ingredients complement and enhance collagen’s positive effect on hair:

  • Hyaluronic acid: A humectant that pulls in water from the atmosphere; it helps your hair retain moisture, drastically reducing dryness and brittleness for shinier, softer, thicker hair
  • Biotin: Vitamin B7; a nutrient your body needs to produce keratin. A 2015 study found that women who took supplemental biotin experienced notable hair regrowth compared to the placebo group. 

  • This is why we’ve formulated our Premium Collagen Peptides with hyaluronic acid and biotin. We’ve also gone the extra step to include vitamin C, a cofactor for collagen synthesis. Because an uptick in collagen production equals a healthier scalp, which supports the growth of thicker hair. 

    And if you’re wondering whether it’s effective, we’ll let our customers’ before-and-after collagen results speak for themselves

    Annelis M: “My hair is sooo much healthier and has filled out especially at the ends. The collagen very clearly works wonders!!”

    Cunie J: “Wow, finally something worked to grow out my bald spot! I'm so impressed”

    Tarsha D: “I suffer really bad from stressed induced alopecia. When I lose my hair it takes about a year to grow back. I had been on these collagen drinks for 2 weeks and my last bald spot has grown insanely! I also have naturally really thick hair, the thickness has doubled which is driving me mental but proves this stuff really does work!”

    So. This way to supreme hair volume

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