Biotin: What It Does, How It Supports Hair, and Why Everyone’s Talking About It

There’s a new(ish) it vitamin in town: Everyone’s talking about biotin and how it’s the key to thicker, fuller hair and strong nails. But what does science say? Should you be taking a supplement? We break it all down.

Biotin at a Glance

Topic	What It Means	What to Know
What biotin is	Biotin, also called vitamin B7, is a water-soluble B vitamin involved in energy metabolism and keratin production.	Your body doesn’t store biotin, so it needs regular intake from food.
How biotin supports hair	Biotin supports normal hair growth and helps maintain healthy hair and nails.	Low biotin levels can contribute to thinning hair and brittle nails.
What research says	True biotin deficiency is uncommon in healthy adults.	There’s limited evidence that biotin supplements improve hair growth if you aren’t deficient.
Diet vs supplements	Most people can meet biotin needs through food alone.	A balanced diet with nuts, legumes, fish, and vegetables is usually enough.
Important cautions	High-dose biotin supplements can interfere with certain lab tests.	Large doses may worsen acne in some people. Always talk to a doctor before supplementing.

What Is Biotin?

Biotin, also known as vitamin B7, is part of the family of B-complex vitamins (maybe you’ve heard of the others: B12, B6). It’s a water-soluble vitamin that’s needed for the production of fatty acids and glucose, which your body uses as fuel.1

Because hair is made of proteins like keratin and requires energy for cell turnover that keeps the hair growth cycle humming along, biotin’s role in metabolism and turning carbohydrates, fats and protein into energy has led to all the interest in its impact on hair health. 

The Biotin-Hair Health Link

Biotin has been linked to healthy nails and skin because it’s involved in your body’s production of keratin, and your hair follicles need a steady supply of keratin to grow healthy hair. Another factor linking biotin to hair health is that there is evidence that lack of biotin can lead to hair shedding and thinning.2

In one study of women who reported hair loss, researchers found that 38% had a biotin deficiency.3 But it’s important to note that it’s uncommon for healthy adults to have a deficiency in biotin.

 

 

What Could Cause You to be Low in Biotin?

There are certain medications (including anticonvulsants) and medical conditions (including inflammatory bowel disease) that can lead to a biotin deficiency.4, 5 Taking antibiotics long-term may also lead to low levels of biotin since antibiotics can disrupt your intestinal microbiome, and one of the sources of biotin production is your gut.6 When these circumstances happen, hair loss is reported as a symptom.

Why Biotin Is So Popular

As we’ve become more aware of hair health and there’s more discussion of hair loss in women and how common it is, there’s been an increasing focus on vitamins and other supplements available over-the-counter that may make a difference.

Biotin is water-soluble, meaning that your body doesn’t store it, as opposed to fat-soluble, which means your body absorbs the vitamin or mineral and stores it in the liver and fatty tissues for long-term use. Water-soluble vitamins and minerals are eliminated daily in your urine, whereas ones that are fat-soluble can build up in your body and potentially become toxic if you take too much. Since biotin is water-soluble, easy to formulate, it’s become a go-to in beauty supplements. 

How To Get Biotin Naturally

Eating a healthy diet with a wide variety of foods (fruits, vegetables, whole grains, nuts, seeds, lean protein) helps you get enough biotin.7

The recommended daily intake of biotin is 30 micrograms a day, and it’s not difficult to get that amount from your diet. Foods that are good sources of biotin include:

Biotin-Rich Food Group	Foods That Provide Biotin	How They Aid Your Hair Health	Additional Benefits
Nuts and seeds	Almonds Walnuts Pecans Sunflower seeds	Supplying biotin and healthy fats	Healthy fats protect the scalp barrier and reduce dryness
Legumes	Beans Lentils Chickpeas Peanuts	Providing biotin and amino acids	Plant protein and fiber help stabilize blood sugar and stress hormones
Mushrooms	Button mushrooms Shiitake Portobello	Contributing biotin and antioxidants	Antioxidants help counter oxidative stress
Fatty fish	Salmon Tuna Sardines	Delivering biotin and omega-3 fatty acids	Omega-3s reduce inflammation and improve scalp circulation
Sweet potatoes	Sweet potatoes Yams	Providing biotin along with beta-carotene	Beta-carotene helps regulate healthy cell renewal
Leafy greens	Spinach Kale Arugula Bok choy	Supplying biotin, folate, and iron	Antioxidants lower inflammation linked to shedding

The Healthy Gut Connection

Your gut also produces biotin, and having a healthy microbiome and gut environment supports healthy biotin levels and hair growth. (You also have a microbiome in your scalp!) Foods that help support a healthy microbiome include:

• Prebiotic-Rich Foods: Asparagus, onions, garlic, bananas, artichokes, beans, lentils, nuts and seeds

• Probiotic-Rich Foods: Fermented dairy (kefir, yogurt with live, active cultures); fermented vegetables (kimchi, sauerkraut)

• Healthy Fats: Foods with mono- and polyunsaturated fats (olive oil, avocado, nuts).

Should You Supplement With Biotin?

While not getting enough biotin can cause brittle nails and thinning hair, research shows that it’s not common for people to have a biotin deficiency. Also, reviews of clinical research show that there are very few good studies saying that taking a biotin supplement improves hair growth in people with normal levels.8

One note of caution: Too-high levels of biotin can skew lab tests for thyroid function and cardiac panels. So before you take a supplement, ask your healthcare provider to check your biotin levels; it’s a simple blood test. 

Biotin vs Keratin Peptides

Two of the most common (and most talked about) products in the supplement aisle that can help with hair thinning and shedding are biotin and keratin peptides. How do they compare?

Comparison Point	OMI Hair Growth Peptides	Pure Biotin Supplements
What it’s made to do	Delivers bioavailable keratin peptides and supporting nutrients that directly strengthen hair structure and support follicle function.	Provides vitamin B7 to support energy metabolism and keratin production indirectly.
How it helps your hair	Supplies the amino acids needed to build keratin fibers, improve elasticity, and reduce breakage while supporting the hair growth cycle.	Helps maintain normal hair growth only when biotin deficiency is present.
How they work	Targets multiple contributors to hair thinning, including stress-related shedding, aging, hormonal shifts, inflammation, and nutrient gaps.	Addresses a single nutrient pathway and does not account for other common causes of hair loss.
Support at the roots	Supports follicle anchoring and collagen IV production, improving follicle stability and the growth environment.	Does not directly support follicle structure or anchoring.
What research shows	Clinical studies show improvements in hair density, strength, shine, shedding reduction, and growth-phase ratios with consistent use.	Evidence is limited for people with normal biotin levels, and deficiency is uncommon in healthy adults.
What’s in the formula	Includes keratin peptides, B vitamins, minerals, and antioxidants designed to work together.	Typically contains only biotin, often at high doses.
Risks and safety	Designed without hormones or high-dose single nutrients.	High doses may interfere with thyroid and cardiac lab tests and may increase acne in some people.
Who it’s best for	People experiencing thinning or shedding related to stress, aging, hormonal changes, or overall hair quality concerns.	Individuals with a confirmed biotin deficiency diagnosed by a healthcare provider.

The Takeaway

Biotin is a B-vitamin that plays a crucial role in metabolizing fats, carbohydrates and proteins; protein helps keep hair, skin and nails healthy. It also supports enzymes called carboxylases, which assist in key metabolic processes, and it contributes to the health of your skin, nerves, and keratin infrastructure. 

Biotin’s role is indirect, supporting metabolic processes rather than supplying structural material to the hair itself.

Keratin peptides, on the other hand, are structural proteins that make up the actual building blocks of hair.

“OMI Hair Growth Peptides have not been evaluated or approved by the FDA to treat any disease. This article is for educational purposes only.”

Frequently Asked Questions

Can low biotin cause hair loss?

Low levels of biotin can lead to hair loss, but only if you’re truly deficient. Studies show that a biotin deficiency can lead to thinning hair and brittle nails but biotin deficiency is uncommon in healthy adults. You’re more at risk for a deficiency if you’re taking certain medications (antibiotics long-term, for example) or have a medical condition that can cause it.

What foods can I eat to boost my biotin levels?

Biotin isn’t hard to get from eating a variety of whole foods. Good sources include nuts and seeds, legumes (lentils and chickpeas), mushrooms, sweet potatoes, salmon and other fatty fish, and leafy greens like spinach. 

Can my gut health affect my biotin levels and my hair?

Yes! Your gut bacteria actually produce biotin, so a healthy microbiome helps keep levels steady. If your gut health is off (say due to a low fiber diet or taking antibiotics), it may reduce biotin production. Eating prebiotic foods (bananas, asparagus, onions) and probiotic foods (yogurt, kefir, sauerkraut) helps support a healthy gut environment, which in turn supports healthy biotin levels and hair growth.