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The Science Behind Biotin And Hair Growth – What You Need To Know

Written by: Anna Misztela, Executive Contributor

Executive Contributors at Brainz Magazine are handpicked and invited to contribute because of their knowledge and valuable insight within their area of expertise.

Executive Contributor Anna Misztela

Biotin, also known as vitamin B7 or vitamin H, is a water-soluble vitamin found naturally in foods such as beef liver, eggs, salmon, avocados, pork, nuts and seeds and sweet potatoes. It is important for our general health because of the role it plays in helping enzymes break down the carbohydrates, proteins and fats in our food. In the USA it is rare to see biotin deficiencies within the population, as most people eat a sufficiently nutritious diet to cover the adequate intake level of 30 mg/day (35 mg/day for lactating women).

capsule vitamins on plastic bottle

Despite this fact, biotin has managed to gain significant hype in the dietary supplement market, and in particular for hair, skin and nails. Recent data ¹ from a survey of over 40,000 participants indicated that 3.9% (1560) used a hair, skin and nails supplement within the last 30 days. Usage was greater for females over males, Blacks and Hispanic/Latinos over Whites, and those with more than a high school education. Total use of these supplements has doubled from 2011-2012 to 2017-2020. As biotin will undoubtedly be an ingredient in the majority, if not all of these supplements, its worth to examine what we know about the science behind its effectiveness (which in comparison to its hype, is surprisingly little).

Can you take too much biotin?

Let’s begin by mentioning an important fact about biotin for which we have solid evidence. Excessive levels of biotin can interfere with the results of some routine thyroid function tests, immunoassay tests and in other tests resulting in the production of a document on the guidance of dealing with biotin interferences in laboratory testing. As a result of this, and the fact that there remains a bit of a knowledge gap about these potential biotin-induced laboratory test interferences with physicians,it is very important that usage of biotin-containing supplements be discussed with your family doctor or any other physician you may encounter during a hospital visit.

Does biotin help with hair growth?

Now let’s move on to the effect of biotin on hair, skin and nails and begin with the results of a somewhat non-scientific, albeit quantitative study. ² The reviews of 16 top biotin products on Amazon were evaluated, and the mean percentage of reviews indicating that the product benefited hair, skin and nails was 27.2%, 2.8% and 15.0%, respectively. Put another way, this means that for the great majority of us, these supplements really had no effect on the appearance of hair, skin and nails, though obviously important factors such as duration and consistency of usage were not mentioned. Also of note was that no products mentioned the FDA warning about interferences with laboratory tests previously discussed, and it was only mentioned by one reviewer. Moving on to reviews and studies incorporating a bit more scientific rigor, the results really do not change. Evidence supporting the use of biotin to remedy skin rashes and hair loss from large scale studies is lacking. In studies where there has been some effectiveness observed, there is frequently an association with some form of biotin deficiency (genetic, gastrointestinal disease, valproic acid usage – commonly used to treat epilepsy or an underlying dermatitis condition). And so simply by bringing the biotin levels in these individuals up to normal values, benefits of supplementation with biotin were observed. In terms of general improvement of hair volume and appearance, the clinical efficacy of biotin supplementation does not seem to be commensurate with its social popularity.

However, if we are discussing biotin supplementation to enhance nail growth and reduce brittleness, the evidence is much stronger. Earlier studies that took place some 30 years ago resulted in a significant fraction of the participants that received biotin supplementation showing a substantial increase in nail plate thickness. More recently, administration of 2.5 mg/day of biotin was found to increase the rate of nail growth compared to a control group that did not receive the supplement.The reason for this is not yet clear, but studies performed in petri-dishes in biological laboratories indicate that biotin promotes epidermal cell differentiation and growth. Other clinical trials have shown a positive effect of oral biotin supplementation in nail thickness, hardness and brittleness. ³ ⁴ A likely factor behind these beneficial effects relates back to the role biotin plays in protein synthesis, and specifically keratin production, which is the main component found in our fingernails.

Final thoughts

To summarize all this information succinctly, what we do know for sure is that biotin can mask the results of several different types of standard medical laboratory tests, so if you are supplementing with biotin we cannot stress how important it is to discuss this with your family doctor or any medical professional you encounter during a hospital visit. Beyond that, there is solid evidence to show that biotin can positively impact nail growth, thickness and brittleness, and this is likely related to the importance of biotin in our body’s production of the protein keratin, which is the main component of our fingernails. Evidence for biotin supporting hair growth does not match its hype however. Most, if not all, studies that do show a positive effect of biotin on hair growth can be traced back to an underlying biotin deficiency in the individual. Further studies with proper control arms and participants with healthy biotin levels are required to effectively determine the benefit (or not) of biotin on hair growth.

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Anna Misztela Brainz Magazine

Anna Misztela, Executive Contributor Brainz Magazine

Anna Misztela’s interest in nutrition analysis and beauty began after she won the Mrs Polonia 2017 and Mrs Polonia World 2018 beauty contests. She then completed a Nutrition Science certification and became a Board-Licensed Esthetician. Her goal was to unlock the mystery of naturally beautiful hair, skin and nails. She was astonished by her discoveries of how sulfur and different types of vitamins work in our body. Since Roman times sulfur baths and sulfur waters have had known health and beauty benefits. Anna has included these compounds in her unique product, which helped many women to transform their hair, improve skin conditions, and get stronger nails. That’s how Beauty&Cutie was born.





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