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Liquid Biotin for Hair Growth: Is It Effective?

Katelyn Hagerty

Reviewed by Katelyn Hagerty, FNP

Written by Nicholas Gibson

Published 10/15/2021

Updated 10/16/2021

If you’ve looked into supplements for stronger, healthier and thicker hair, you’ve almost certainly heard of biotin.

Biotin, or vitamin B7, is a water-soluble vitamin that supports hair and nail growth. It’s found in a variety of biotin-rich foods, such as eggs, bananas and milk. 

It’s also available as a supplement in products such as Biotin Gummies.

Over the last few years, liquid biotin supplements have grown in popularity. Lots of these supplements make big claims about their ability to stimulate hair growth and promote strong, healthy skin and nails.

Read on to learn what these supplements are, as well as how they work to promote better hair and nail growth. 

You’ll also find details on the science behind liquid biotin to see whether it’s actually as effective as many supplement manufacturers claim. 

Finally, we’ve detailed other techniques, below, that you can use to stimulate growth and promote thick, healthy hair.

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Liquid biotin is exactly what it sounds like — the popular vitamin biotin in liquid form. Biotin liquid supplements usually come in a flavored liquid, with a dropper allowing you to take in a precise amount of liquid with each serving.

Biotin itself is a B-vitamin that’s used in many important processes within your body. It helps to break down substances such as fats and carbohydrates. 

Biotin is also involved in the regulation of gene expression, cell signaling and the function of amino acids within your body.

Like with many other essential vitamins, when your body is deficient in biotin, things don’t quite work as well as they should. 

In fact, it’s common for people with biotin deficiency to develop brittle nails, thinning hair, irritated skin and, in the case of severe deficiency, hair loss that affects the entire body.

Because of its popularity, biotin has been extensively studied as a supplement for treating and preventing hair loss.

Although research is mixed overall, several studies have found that biotin supplements help stimulate healthy hair growth in certain situations.

For example, in a study published in the Journal of Clinical and Aesthetic Dermatology in 2012, a group of women with self-perceived thinning hair were sorted into two groups. 

One group of women was treated with an oral supplement containing biotin and zinc, while the other group received a non-therapeutic placebo. 

This study took place over 180 days, with the researchers assessing hair growth after 90 and 180 days. 

After 90 days, the women who used the supplement roughly doubled their hair count, while the women who used the non-therapeutic placebo showed a very small reduction in hair density.

The women in the biotin and zinc group maintained their results at the end of the study, with a small increase in hair density observed at 180 days.

In short, the biotin and zinc supplement produced a measurable increase in hair count, with the results visible after 90 days. The women also reported improvements in their hair shine and skin health.

However, there are a few issues here that need to be pointed out. The first is that the women in the study all suffered from thinning hair. 

While the biotin supplement clearly helped them, it may not have the same effect in people without existing signs of hair thinning.

Put simply, while biotin seems to help thin hair become more dense, there isn’t much in the way of evidence that it can improve the density of healthy hair. 

The second issue is that the supplement contained a mix of biotin and zinc. Since hair loss is a well-known sign of zinc deficiency, it’s possible that the zinc contributed to some of the new hair growth, rather than just the biotin.

Overall, the study is interesting research that clearly points towards biotin supplements helping with hair growth, at least in women with existing hair loss. 

Other research on biotin is mixed. A study published in the International Journal of Trichology in 2016 found that 38 percent of women with hair loss also have a biotin deficiency.

On the other hand, a review published in Skin Appendage Disorders found that while biotin produced skin and nail improvements in people with biotin deficiency, it doesn’t appear to produce any significant improvements in healthy people.

So, does liquid biotin work? If you have a biotin deficiency or thinning hair, the research certainly suggests that biotin is effective.

However, there’s little evidence that biotin produces improvements in hair growth in people with good existing hair health. 

Liquid biotin supplements are widely available from health food stores, drug stores and online vendors such as Amazon. 

Pricing varies from brand to brand, with most products available for between $15 and $30 per bottle.

Taking liquid biotin is simple. Most products come with a dropper, allowing you to measure the correct amount of liquid for each serving. 

Use the dropper to carefully squeeze the liquid biotin under your tongue, and then hold it there before swallowing. 

Make sure to check the dosage (and suggested holding time) on the product label before using any liquid biotin supplement. 

Biotin is generally a safe supplement. When it’s taken at the recommended dosage, side effects are mild and uncommon. 

Currently, there’s no evidence to suggest that biotin is toxic to humans even when taken in large amounts.

However, it’s important to be aware that large doses of biotin can cause false results for certain diagnostic tests.

More specifically, taking large amounts of biotin from supplements can interfere with tests used to check thyroid hormone levels. 

This means that if you use a biotin supplement at a high dose, it’s possible that you could be misdiagnosed with a thyroid disorder.

This is an important problem to be aware of, especially because many liquid biotin supplements contain extremely high doses of biotin. 

For example, some liquid biotin supplements available online and in drug stores contain 25,000 micrograms (mcg) of biotin per serving.

To put this biotin dose in perspective, hims & hers Biotin Gummies contain 300 micrograms of biotin per serving — an amount that’s much closer to the 30mcg Daily Value (DV) for biotin recommended by the Food and Drug Administration.

If you use a biotin dietary supplement, especially a high-strength one, it’s important to tell your healthcare provider about it if you ever take a blood test. 

This will help them properly interpret your test results and prevent misdiagnosis.  

Biotin supplementation can offer benefits, especially if you have thinning hair that’s caused by a nutritional deficiency. 

However, taking a biotin supplement isn’t the only way to prevent hair loss and improve hair growth — nor is it necessarily the most effective on its own. 

If you’re starting to notice hair thinning, you’ll get the best results by combining supplements such as biotin with FDA-approved hair loss medication.

When it comes to female hair loss, the most effective treatment on the market is the topical hair loss medication minoxidil (commonly sold under the brand name Rogaine®). 

Minoxidil works by moving your hair follicles into the growth phase of the hair growth cycle, and by stimulating blood flow to your scalp. 

Research shows that it produces real improvements in hair growth and density, especially when it’s used over the long term.

You can purchase minoxidil solution and minoxidil foam online, and both forms of the treatment can stimulate hair growth and treat thinning hair. 

Another way to stop hair loss and strengthen your hair is by using a women’s hair loss shampoo to control shedding and wash away excess sebum that can damage your hair follicles.  

The hers Complete Hair Kit includes minoxidil, biotin, shampoo and conditioner, making it easy to target hair loss and stimulate growth from every possible angle. 

Beyond medications and hair care products, good habits can promote optimal growth and keep your hair strong, smooth and thick. Try to eat a balanced, healthy diet, limit stress (which could cause stress-related hair shedding) and take care to be gentle when you style, color or brush your hair. You may have heard about certain nutrients being beneficial for growth, such as vitamins A and C and silica for hair.

This guide to how you can thicken your hair lists 12 simple, effective techniques to help improve your hair growth and thicken your head of hair. 

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Research shows that biotin supplements help to improve hair growth in women with thinning hair. 

However, there’s little research available about the effectiveness of liquid biotin or other biotin products for those with hair that’s already healthy. 

If you’re looking for a supplement to add to your hair growth routine, liquid biotin may be a good choice. 

Just be aware that you’ll need to let your healthcare provider know about it if you ever get a blood test. 

To get started treating hair loss and promoting optimal hair growth, check out this complete range of women’s hair loss products online.

You can also learn more about why female hair loss occurs and what you can do to stop it in this full guide to the best hair loss treatments for women

If you’re experiencing noticeable hair thinning or hair loss, you may want to consult with a healthcare professional, too, to learn more about what’s causing your issue, as well as your best treatment options. 

8 Sources

Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references.

  1. Biotin. (2021, August 19). Retrieved from
  2. Biotin. (2021, March 29). Retrieved from
  3. Glynis, A. (2012, November). A Double-blind, Placebo-controlled Study Evaluating the Efficacy of an Oral Supplement in Women with Self-perceived Thinning Hair. The Journal of Clinical and Aesthetic Dermatology. 5 (11), 28–34. Retrieved from
  4. Almohanna, H.M., Ahmed, A.A., Tsatalis, J.P. & Tosti, A. (2019, March). The Role of Vitamins and Minerals in Hair Loss: A Review. Dermatology and Therapy. 9 (1), 51–70. Retrieved from
  5. Trüeb, R.M. (2016, April-June). Serum Biotin Levels in Women Complaining of Hair Loss. International Journal of Trichology. 8 (2), 73–77. Retrieved from
  6. Patel, D.P., Swink, S.M. & Castelo-Soccio, L. (2017, August). A Review of the Use of Biotin for Hair Loss. Skin Appendage Disorders. 3 (3), 166–169. Retrieved from
  7. Badri, T., Nessel, T.A. & Kumar, D.D. (2021, April 13). Minoxidil. StatPearls. Retrieved from

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.

Katelyn Hagerty, FNP

Kate Hagerty is a board-certified Family Nurse Practitioner with over a decade of healthcare experience. She has worked in critical care, community health, and as a retail health provider.

She received her undergraduate degree in nursing from the University of Delaware and her master's degree from Thomas Jefferson University. You can find Katelyn on Doximity for more information.

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