It’s probably safe to say that anyone who’s ventured even slightly into the world of hair loss treatment has heard of biotin—the miracle supplement for hair, skin, and nails. A quick Amazon search tells us that the bestselling biotin softgels have well over 75,000 reviews, largely positive; “My hair has never looked better!” and so on and so forth. So of course it’s easy, and so tempting, to hit that purchase button, because surely tens of thousands of people can’t be mistaken. And who could forget those Kardashian-endorsed hair vitamins?
We know better than most how devastating a toll hair loss can have on an individual. But it’s important to take a step back and examine supplements like biotin with serious caution. There’s a lot of misinformation out there on the Internet, and a lot of companies specifically targeting vulnerable customers with hair insecurities, so today we’re going to take a brief dive into the science behind biotin supplements. Does oral biotin really work to replenish hair? Is it worth the money? Would the Kardashians ever lie?
So first things first: what exactly is biotin? Biotin is a vitamin; no more, no less. Specifically, biotin—known also as Vitamin B7 or Vitamin H—is a water-soluble B vitamin. Let’s break that down into simpler terms. A vitamin is an essential nutrient needed for the proper functioning of the metabolism. The defining characteristic of a vitamin is that it cannot be synthesized within the body itself—that’s why to get Vitamin C, we drink orange juice, and to get Vitamin D, we spend some time out in the sun. When we have vitamin deficiencies, that means that we aren’t getting enough of a particular vitamin from our diet or everyday activities, which is when it becomes necessary to supplement with the vitamin capsules or softgels you can buy at any supermarket or pharmacy. There are two types of vitamins: fat-soluble and water-soluble. Fat-soluble vitamins are stored in the fatty tissue and the liver, and can stay in the body for days or even months at a time. In contrast, water-soluble vitamins are not stored in the body, but are urinated out. Biotin, like all B vitamins, is water-soluble.
Now, which parts of biotin supplement advertising is based in fact? Well, biotin is essential for the body to metabolize proteins, fats, and carbohydrates, but its connection to the beauty industry lies in its contribution to the formation of keratin, a structural protein in hair, skin, and nails. So is there a connection between biotin and hair? Absolutely. And as a water-soluble vitamin, it’s definitely important to maintain a regular biotin intake. But what’s valuable to remember is the directionality of causation. In other words, does biotin deficiency reduce the quality of hair, or does excessive biotin significantly improve hair?
The answers: yes … and no. That is, a marked deficit of biotin in the body is likely to present itself in the form of brittle or unmanageable hair, but the key word here is deficit. The truth is, the vast majority of individuals are not biotin-deficient. We take in biotin simply by eating a balanced diet, as sources of biotin include eggs, legumes, nuts, meats, fruits, and vegetables—basically, most people will be consuming a sufficient amount of biotin on a daily basis without ever thinking about it. The exceptionally rare individual who genuinely suffers from biotin deficiency may see improvement via supplementation, but this is not the average person. When someone who does not have a deficiency takes in an excess amount of biotin, there is little to no discernible impact. Remember that biotin is water-soluble—this means that if you are not deficient and you choose to consume a daily supplement, all excess will leave the body through the urine. The Food and Nutrition Board at the National Academies of Sciences, Engineering, and Medicine considers an adequate daily intake of biotin to be around 30 mcg—meanwhile, commercially available biotin supplements are often as much as 10,000 mcg per capsule or softgel. In a 2017 issue of the Journal of Drugs in Dermatology, Teo Soleymani, Kristen Lo Sicco, and Jerry Shapiro described the modern public interest in biotin supplementation as an “infatuation”; upon an in-depth review of existing scientific literature, they found not just minimal evidence, but near-total lack of evidence to support the use of biotin supplementation to improve hair quality or quantity. This means no clinical trials conducted on the efficacy of biotin in the treatment of any type of alopecia, and no clinical trials on the efficacy of biotin in improving hair quality in individuals without alopecia. In the same year, another literature review for the journal Skin Appendage Disorders found only 18 reported cases of successful biotin use for hair and nails, and every single one was in a patient with biotin deficiency.
So how are there tens of thousands of people in Amazon reviews raving about the effect of 10,000-mcg biotin supplements on their hair? Statistically, it’s astronomically unlikely that every single five-star review is from someone with a serious biotin deficiency (though of course some very well might be!), so what’s going on?
The hard truth is that often, we see what we want to see. The human brain has a tendency of fooling itself, especially when it comes to something that causes as much insecurity as hair loss. And of course, the placebo effect is very real, and can work even when we’re aware that it’s a placebo. So no, all those rave reviews about biotin aren’t just lying to you, but take them with a massive grain of salt. (But the Instagram influencers shilling hair vitamins probably aren’t taking them, just so you know.)
This isn’t to say that you can’t take biotin supplements if you want to, only to be aware of the limitations. If you’re experiencing serious hair loss, it never hurts to ask for a medical opinion, including for bloodwork to see if you might be one of the few with a real biotin deficit. In that case, biotin supplements probably will do some good. Otherwise, if taking supplements makes you feel better, there’s nothing wrong with that—mental and emotional well-being can have a major impact on your physical appearance, including your hair! Just remember that supplements and their ingredients are not regulated by the FDA, so be sure to read each label carefully for anything out of the ordinary.
Your diet guru,
Melissa A.
If you’d like to read through the referenced journal articles in this post, feel free at the below links!