When starting a supplement routine, there is no shortage of questions to answer.
One of the more common questions we tend to get is what supplement ingredients play well together. Well, that comes down to two additional questions.
First is are they safe and stable to take together—meaning they won't have counterproductive interactions or lessen each other's impact.
The second is do they work toward a common health support goal or even synergistically to help each other be more effective and bioavailable?
Well, certain actives tend to be common supplement duos, as is the case with collagen and biotin. So let's get into how and why they're formulated together.
What are the benefits of a collagen supplement?
Collagen is the most abundant protein in the skin—and a protein that shows up in a lot of other places, too, like the joints, bones, and gut lining.
Because it has several roles all throughout the body, taking a collagen peptide supplement can provide several all-over benefits from your hair to your bones.*
We go into collagen supplements in pretty impressive detail in our guide (if we do say so), but a quick rundown can help:
Skin, hair, and nails
Studies have shown that taking collagen peptides will support skin elasticity and hydration levels and promote youthful texture1.*
Collagen supplements also provide many of the amino acids and nutrients needed for hair growth: "Amino acids are the building blocks for keratin, the material that hair is made of," according to board-certified dermatologist Joshua Zeichner, M.D.
Yes, for the body to build keratin, it needs several types of amino acids, many of which are found in collagen peptides2. In fact, the main amino acid in keratin is proline—which is readily found in many collagen supplements.*
The beauty supplement can also help nail strength; one study found that when patients took collagen daily for 24 weeks, it helped support their nail health3, including better growth rates, reduced breakage, and improved appearance.*
Research shows that collagen can help support your gut health4.* As gut health specialist Vincent Pedre, M.D., told mbg, "For the same reasons collagen helps repair and grow muscle tissue, it serves as an excellent nutrient source for supporting the rapidly dividing cells that line the interior of the gut."*
Ashley Jordan Ferira, Ph.D., RDN, vice president of scientific affairs at mindbodygreen, further explains that "in addition to providing key amino acids to fuel the gut, collagen peptides are also thought to support tight junctions5 in the GI tract, in other words, preserving the integrity of the gut lining."*
Collagen is found in all connective tissues that make up our joints (including ligaments and tendons), and collagen supplements provide almost 20 unique essential and nonessential amino acids to support natural levels throughout the body.* Healthy connective tissue structure helps support joint health and function.
Muscles and bones
Another found that supplements can support skeletal muscle mass and strength8.*
In fact, according to Nour Zibdeh, M.S., RDN, CLT, "Collagen can also support lean muscle and help improve body composition."*
Of course, given bone growth and development—and the lengthy timeline associated with it—it's a harder area to study, but it seems promising.
What are the benefits of a biotin supplement?
Biotin is an essential water-soluble B vitamin—vitamin B7, specifically. B vitamins fuel many delicate, intricate pathways in the body.
Biotin is critical for the daily utilization of fats, carbs, and amino acids (ahem, like those found in collagen supplements) for energy (ATP).*
And while biotin has earned its place in a B-complex, most people supplement with biotin with beauty in mind.* Most products with biotin are cosmeceutical in nature, and thus that's what we'll focus on here.
Now, before we dive into the benefits of biotin, it's important to note a few things. The first is that cases of biotin insufficiency and frank deficiency are quite rare in our modern world.
The second is that the research about this supplement's benefits isn't as robust as that for collagen.
"The biotin and hair, skin, and nails association and evidence candidly carries more anecdotal clout than published science as a stand-alone nutrient, but the biological mechanism of its support is enough evidence for most people,"* says mbg's Ferira. "Then when their hair and nails improve, that's additional proof."*
In one small study, women reported hair growth when supplementing with biotin (as part of a multi-ingredient supplement) when compared to those given a placebo.*
Can you take them together?
Let's revisit the intro. Remember how it's important to consider safety and efficacy when deciding to take two supplement nutrients or bioactives together? Well, biotin and collagen pass on both fronts.
"Collagen and biotin are both safe, well-tolerated cosmeceutical bioactives, supporting hair, skin, and nail health,"* says Ferira. "But they have their own unique and individual mechanisms for structurally and functionally doing that, hence the reasonable potential for synergy in combining them. Both collagen- and biotin-containing foods and supplements provide key nutrients or building blocks for our body. Collagen provides macronutrient—protein—nourishment and critical amino acid building blocks. Biotin provides an essential water-soluble B vitamin (B7), which acts as a versatile cofactor in a variety of bodily functions."*
Research shows this too. While biotin hasn't been as well studied on its own, there's a decent amount of clinical research studying the two ingredients together.
For example, this study demonstrates that taking both has a positive impact on skin hydration, elasticity, smoothness, and density13.*
Another clinical intervention found improved collagen structure of facial skin14 via objective microscopy results, plus positive subjective results for skin's appearance (e.g., elasticity, wrinkles, and texture) on hands, neck, legs, belly, and décolletage.*
As far as beauty supplements go, combining biotin and collagen together is a safe bet.*
Not only that, but research suggests they may help each other out too. Now, after reading all this, you likely are in the market for a new supplement, so check out our list of the best collagen supplements around.
Alexandra Engler is the beauty director at mindbodygreen and host of the beauty podcast Clean Beauty School. Previously, she's held beauty roles at Harper's Bazaar, Marie Claire, SELF, and Cosmopolitan; her byline has appeared in Esquire, Sports Illustrated, and Allure.com. In her current role, she covers all the latest trends in the clean and natural beauty space, as well as lifestyle topics, such as travel. She received her journalism degree from Marquette University, graduating first in the department. She lives in Brooklyn, New York.