Does Biotin Help Eyelashes and Eyebrows Grow? The Surprising Truth

October 7, 2025 •

4 min read

According to a 2017 study, biotin deficiency was found in 38% of women complaining of hair loss, highlighting a potential link between low levels and thinning hair. But the question remains: does biotin help eyelashes and eyebrows grow for everyone, or only those with a deficiency?

Quick Summary

Biotin supports keratin production, a key protein for hair, but its effect on eyelash and eyebrow growth is limited to individuals with a confirmed deficiency. For healthy people, benefits are anecdotal and a balanced diet is more impactful. Proper usage and potential lab test interference should be considered.

Key Points

Limited Evidence for Healthy Individuals: Biotin supplements have limited scientific evidence for promoting hair growth in non-deficient individuals, including eyelashes and eyebrows.
Effective for Deficiencies: Biotin is most effective for hair growth in individuals with a diagnosed biotin deficiency, a condition that is rare in the general population.
Supports Keratin Production: Biotin's primary function related to hair is its role in supporting the production of keratin, the main protein component of hair, skin, and nails.
Consider Topical and Oral Options: Topical biotin serums may help strengthen and nourish hairs from the outside, while oral supplements work systemically, though with minimal effect for those without a deficiency.
Focus on a Balanced Diet: For most people, maintaining healthy hair, including lashes and brows, is best achieved through a balanced diet rich in other nutrients like iron, zinc, and omega-3s.
Risk of Lab Test Interference: High doses of biotin supplements can interfere with certain lab test results, especially those for thyroid hormones, necessitating a conversation with a healthcare provider before testing.

Understanding Biotin's Role in Hair Health

Biotin, also known as vitamin B7 or vitamin H, is a water-soluble B-complex vitamin that is essential for cellular metabolism. A primary function of biotin is its role as a cofactor for enzymes that produce keratin, the fundamental protein structure of hair, skin, and nails. This critical function is why biotin is so closely associated with hair health. When the body has a sufficient amount of biotin, it can efficiently produce keratin, which helps to maintain the strength and resilience of hair shafts. However, unlike fat-soluble vitamins, the body does not store excess biotin for long, so a regular intake is necessary to maintain optimal levels.

The Link Between Biotin and Hair Loss

A deficiency in biotin is rare in healthy individuals who consume a balanced diet, as many common foods contain it. Intestinal bacteria can also produce biotin. When a true deficiency does occur, however, symptoms can manifest as thinning hair, brittle nails, and specific skin rashes, among other issues. Conditions like certain genetic disorders, chronic alcohol use, malabsorption issues from intestinal diseases, or taking specific medications can increase the risk of a deficiency. In these rare cases, supplementation can be effective in reversing hair thinning and restoring health.

Does Biotin Actually Grow Eyelashes and Eyebrows?

This is where the popular perception of biotin often diverges from the scientific consensus. For individuals with a diagnosed biotin deficiency, taking supplements can indeed help with hair growth, including eyelashes and eyebrows, by correcting the underlying problem. For those who are not deficient, however, the benefits are less clear. While biotin supports the keratin infrastructure, there is limited clinical evidence that supplemental biotin directly boosts hair growth in healthy individuals. Many reported improvements among non-deficient users are anecdotal.

The logic is simple: if your body already has enough biotin to produce keratin, adding more through supplements is unlikely to accelerate the growth cycle of your lashes or brows. At most, it might help strengthen the existing hairs, making them less prone to breakage and allowing them to reach their natural maximum length, which could create the appearance of fuller, healthier lashes and brows. Genetics and other factors are the primary determinants of hair length and thickness.

Topical vs. Oral Biotin for Lash and Brow Growth

Both oral and topical methods exist for delivering biotin, each with different considerations for effectiveness and application.

Oral Biotin Supplements

Mechanism: Work systemically to support overall keratin production from the inside out.
Effectiveness: Most beneficial for those with a deficiency. Minimal scientific evidence for promoting growth in healthy individuals.
Dosage: Supplements contain high doses (e.g., 2,500-10,000 mcg), far exceeding the recommended daily intake of ~30-35 mcg.

Topical Biotin Serums

Mechanism: Applied directly to the lash and brow line to nourish hair follicles locally.
Formulation: Often include other beneficial ingredients like peptides, vitamins, and natural oils to hydrate and protect delicate hairs.
Effectiveness: May help fortify existing hairs and reduce brittleness, though direct promotion of new growth is not clinically proven.

Beyond Biotin: A Holistic Approach to Lash and Brow Health

For most people, a balanced and nutrient-rich diet is a more reliable way to support healthy hair growth than relying solely on high-dose biotin supplements. Other vitamins and minerals play equally important roles in the hair growth cycle and overall hair quality.

Nutritional Support for Healthy Hair Growth

Iron: Deficiency can cause hair loss. It helps carry oxygen to hair follicles.
Zinc: Essential for hair tissue growth and repair.
Omega-3 Fatty Acids: Contribute to improved circulation to hair follicles and maintain hair moisture and shine.
Vitamin E: Acts as an antioxidant, protecting follicles from damage.
Vitamin C: Necessary for collagen biosynthesis, which supports hair structure, and also helps with iron absorption.

Best Practices for Healthy Lashes and Brows

Gentle Makeup Removal: Avoid harsh scrubbing. Use a gentle, oil-based remover to prevent breakage.
Moisture and Care: Consider using a natural oil like castor oil to keep hairs supple and moisturized.
Avoid Over-Plucking: Excessive plucking can damage hair follicles and lead to permanent thinning.
Stay Hydrated: Drinking enough water is crucial for overall health, including hair, skin, and nails.

Comparison Table: Biotin Supplements vs. Natural Diet


Feature	Biotin Supplements	Natural, Biotin-Rich Diet
Effective For	Individuals with a confirmed biotin deficiency or specific pathological hair conditions.	All healthy individuals seeking to maintain optimal hair health.
Effectiveness in Healthy Individuals	Limited evidence for promoting growth; mainly anecdotal.	Sufficient for meeting the body's keratin-production needs.
Potential Side Effects	High doses can interfere with lab tests, such as those for thyroid hormones. Some may experience mild skin or digestive issues.	Generally none, provided a balanced diet is maintained.
Dosage	High, often 2,500–10,000 mcg/day.	Adequate Intake (AI) of ~30-35 mcg/day, easily met through food.
Cost	Can be an ongoing expense for purchasing supplements.	Primarily covered by a normal, healthy food budget.

Conclusion: The Final Verdict on Biotin

While biotin's role in the production of keratin, the protein that makes up hair, is undeniable, the idea that high-dose supplementation will miraculously grow eyelashes and eyebrows is largely a myth for the average healthy individual. The most significant benefits are seen in those with a clinical biotin deficiency, which is quite rare. For most people, a balanced, nutrient-dense diet provides all the biotin needed to support hair growth and strength naturally. A holistic approach that combines proper nutrition with gentle care and avoiding damaging habits offers a far more effective strategy for achieving and maintaining healthy, full lashes and brows. Before starting any new supplement regimen, especially high-dose biotin, it is wise to consult a healthcare professional to rule out underlying issues and ensure it is the right path for your specific needs, particularly due to the potential for lab test interference. For more in-depth information on the use of biotin for hair loss, consult trusted medical sources.

Frequently Asked Questions

For healthy individuals, there is limited evidence that biotin supplements will significantly increase the length or thickness of eyelashes and eyebrows. Benefits are more noticeable for those with a biotin deficiency, which is rare.

Biotin is crucial for the production of keratin, the protein that makes up the structure of your hair, skin, and nails. By supporting keratin, biotin helps maintain the strength and resilience of hair.

Symptoms of a biotin deficiency can include hair thinning or loss, brittle nails, and skin rashes. However, a true deficiency is rare in healthy people. If you suspect a deficiency, consult a healthcare professional for diagnosis and testing.

While excess biotin is generally excreted by the body, high doses can interfere with certain lab tests, particularly those for thyroid hormones. Always inform your doctor if you are taking biotin supplements before a blood test.

The best option depends on your needs. For non-deficient individuals, a balanced diet is key. Topical serums may help fortify hairs externally. Supplements are most beneficial for correcting a diagnosed deficiency.

Beyond biotin, other vital nutrients include iron, zinc, omega-3 fatty acids, and vitamins C and E. A well-rounded diet covering these nutrients supports overall hair health.

In cases of a confirmed biotin deficiency, improvements might be seen after 3–6 months of consistent supplementation. For those without a deficiency, results are unlikely to be dramatic.