Biotin has been quietly riding a decades-long reputation as the supplement that grows your hair and strengthens your nails. The gurus who looked into it closely came back with a very different picture: not just that the hair claims fall apart under scrutiny, but that taking biotin can create a genuinely serious problem for anyone having blood tests. A Guru Score of 0% tells you where those experts landed.
Do skincare experts recommend Biotin?
What unites almost all of these takes is a concern most shoppers have never considered: biotin interferes with a surprisingly wide range of blood tests, including the ones used to check your thyroid, diagnose a heart attack, and screen for prostate cancer. That interference can push results falsely high or falsely low, which means a doctor could conclude you have a condition you do not have, or miss one you do. The FDA has issued warnings on exactly this, and the gurus note that even low doses can cause the problem and that the disruption can linger for several days after you stop taking biotin. As for the reason most people buy it in the first place, the experts were equally unimpressed: genuine biotin deficiency is extremely rare, and without a true deficiency, the research backing these supplements is very thin.
How do the experts rate Biotin?
5 skincare experts weighed in on Biotin, giving it a Guru Score of 0%. 0 approve of it, 1 lands on a mixed take, and 4 would skip it.
Where do skincare experts disagree on Biotin?
The gurus who weighed in were close to unanimous. One stopped short of a flat no rather than landing in clear opposition, but even that take carried no recommendation to use biotin. There was no camp arguing for the supplement's benefits.
"I do not recommend this because of the potential harms from biotin supplementation. Laboratory test interference is the most important risk that you really need to understand. Biotin interferes with many common blood tests including thyroid function tests like TSH, T3 and T4. It can interfere with troponins which are used to diagnose heart attacks, hormone tests like parathyroid hormones, vitamin D and prolactin. It can interact with prostate specific antigen or your PSA test, brain natriuretic peptide or BNP used for a heart failure test. These interferences can cause falsely high or falsely low results potentially leading to misdiagnosis of thyroid disease. You might appear to have hyperthyroidism when you really don't or a misdiagnosis of a heart attack and incorrect treatment decisions. The FDA has even issued warnings about biotin interference with lab tests. Even at really low doses of supplementation, you can still have problems. The interference can last for several days after you stop taking biotin. Other considerations before you take a biotin supplement include the fact that they can be expensive and provide no proven benefit."
"Using a Biotin supplement to grow your hair [...] is a hair care myth that just won't go away. [...] If you are truly deficient in biotin, supplementing with biotin will help you grow your hair, however it is exceedingly rare, so rare that I have never had a patient be biotin deficient. [...] The reality is that a product doesn't work because it has biotin in it; it's because of the entire complex that exists."
"There isn't actually a lot of science behind biotin"
Is Biotin worth it?
What the experts would tell you, taken together, is to leave biotin off the shopping list. The hair-growth story is a myth for the vast majority of people, because genuine biotin deficiency is, as one expert put it, exceedingly rare. The more pressing reason to step back is the lab-test interference: anyone taking biotin and due for blood work may want to flag it to their doctor, since the experts found the disruption can last days even after stopping. A Guru Score of 0% reflects how firmly these experts feel about it.
The gurus who weighed in
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This guide reflects what 5 skincare experts said about Biotin across their videos, aggregated by The Guru Index. The Guru Score is our read on how warmly the experts talk about it. It is general information, not medical advice.