Biotin vs. Collagen: What Are the Differences?

If you’re trying to promote hair growth or strengthen your nails, you’ve probably come across biotin and collagen in your quest.

Although both are common ingredients in hair and nail supplements, they are vastly different compounds that do distinctive things in the body.

In this article, we’ll take a closer look at the differences between biotin and collagen, how they benefit health, and which one has more evidence supporting its use for healthy hair, skin, and nails (spoiler alert: it’s not biotin).

What Is Biotin?

Biotin is a B vitamin (B7) involved in metabolic processes, gene regulation, and cellular signaling. 

It primarily helps to break down carbs, fats, and proteins from the foods we eat into absorbable molecules that we can use for energy. 

Biotin is found in many foods, including meat, fish, eggs, nuts, seeds, sweet potatoes, and beans, and most people consume adequate amounts of biotin in their diet.

What Is Collagen?

Collagen is the most abundant protein in our bodies, contributing to skin elasticity, nail growth and strength, joint mobility, and bone density.

Although the body naturally produces collagen, we make about 1% less of it each year after turning 40.

Up to 30% of all the proteins in your body are collagen—including up to 70% of skin, hair, nails, and almost 100% of connective tissues are made from collagen.

While collagen contains 19 different amino acids, it is formed primarily by glycine, proline, and hydroxyproline, which are not commonly consumed in a typical Western diet. 

Proline and hydroxyproline support skin elasticity by facilitating the growth of dermal fibroblasts—the primary cell type in skin connective tissue—while glycine is essential for gut health and joint, tendon, and ligament functioning and mobility.

However, it’s important to note that collagen is not a complete protein (meaning it does not contain all nine essential amino acids that our bodies don’t produce on their own)—it only has eight.

Nearly 28 different types of collagen have been identified. Still, types I through V are the most abundant in the body, and types I, II, and III are the types you’ll typically find in a collagen supplement.

• Type I: The most prevalent form in the body, this type provides a fibrous structure to our skin, nails, hair, bones, tendons, connective tissues, and ligaments. Type I collagen is typically considered the best type for promoting healthy skin. 
• Type II: This type is found mainly in the cartilage, which helps the joints to remain fluid and mobile. 
• Type III: Commonly found in the muscles, blood vessels, cartilage, and reticular fibers, like bone marrow.
• Type IV: Found in the basement membrane, a matrix of tissues that forms a barrier where cells meet connective tissues. 
• Type V: This type is found in the placenta, hair, the corneal stroma of the eye, and various other cell surfaces. 

Some collagen protein powder products (like Ancient Nutrition Multi Collagen) also utilize Types VII, VIII, X, XII, and XXII collagen. For a list of our favorite collagen powders, check out this article.

In addition to the different types, there are collagen supplements from varying animal sources, including from the bones, hides, and cartilage of chickens, pigs, and cows, the scales and skin of fish (marine collagen), or eggshell membranes.

Biotin Vs. Collagen Benefits

Biotin and collagen have plenty of health benefits, but collagen seems to produce more noticeable effects in supplemental form.

Biotin Health Benefits

The main functions and benefits of biotin include:

• Metabolizing fats, carbohydrates, and proteins 
• Cellular signaling and gene regulation
• Hair growth in people who are biotin deficient or have uncombable hair syndrome
• Nail growth in people who are biotin-deficient or have brittle nail syndrome
• Supporting embryonic and fetal development 

While many people take biotin for skin, nail, or hair health, the research behind these claims is slim. 

One older study from 1993 found that 63% of participants had clinical improvement in brittle nails when taking biotin supplements for six months.

In more recent years, a 2017 review of 18 studies found that people with biotin deficiency, brittle nails, or uncombable hair syndrome experienced hair- or nail-related benefits from biotin, while the healthy population did not. 

The theory behind why biotin could benefit hair and nails is reasonable enough: it’s thought that biotin stimulates keratin production, which is a vital protein that acts as a structural component for hair and nails.

However, while there is plenty of anecdotal evidence circling the internet, there needs to be more conclusive research showing that biotin supplements increase hair growth or nail strength in healthy people.

Collagen Health Benefits

The leading health benefits of collagen include:

• Skin health
• Joint mobility
• Bone density
• Hair and nail health 

Collagen and Skin Health

Skin health is likely the most-studied aspect of supplemental collagen, as the collagen protein is a significant part of the extracellular matrix, a structural component of the skin’s dermis. 

With age, collagen becomes fragmented rather than compact, which reduces the skin’s elasticity and can contribute to wrinkles. 

Collagen contains proline and hydroxyproline, which improve skin elasticity by stimulating the growth of dermal fibroblasts—cells that generate connective tissue and elastic fibers.

In a meta-analysis of 19 studies, people who took hydrolyzed collagen supplements for an average of 90 days had improved skin hydration and elasticity and wrinkle reduction compared to people taking a placebo. 

In another study, women aged 40 to 60 who took 1g of type I collagen peptides daily for 12 weeks experienced improvements in skin hydration and elasticity with reduced wrinkle appearance.
A third study with 45- to 60-year-old women found that 12 weeks of supplemental marine collagen led to a 35% reduction in wrinkle score compared to their baseline. Marine collagen users also had a 23% improvement in skin elasticity, a 25% increase in firmness, and a 14% increase in hydration compared to women taking a placebo.

Collagen and Hair and Nail Health

Less research looks at collagen’s effects on hair and nail health. 

The main protein component of hair is keratin, which contains large amounts of the amino acids glycine and proline found in collagen.

When the body lacks keratin, hair loss or thinning occurs—so, like with biotin, collagen consumption could help with keratin production. 

In a study with 88 middle-aged adults, consuming hydrolyzed eggshell membrane (which is rich in collagen) improved hair thickness and growth and reduced hair breakage within 12 weeks (in addition to reducing the appearance of crow’s feet). 

Other research has looked at the effects of marine collagen on hair growth using in vitro (test tubes) and animal models. In test tubes, marine collagen enhanced hair regrowth and the growth of human dermal papilla cells (cells that induce new hair follicle formation). 

In the animal model, giving collagen to mice enhanced hair regrowth and human dermal papilla cell proliferation more so than mice that received a hair loss medication. 
There is less research on nails, but one study found that collagen increased nail growth rate by 12% and decreased the frequency of broken nails by 42% after 24 weeks.

Biotin Vs. Collagen FAQs