Is Biotin good or bad for you and does Biotin affect thyroid?

I’ve been using Vegamour (with Biotin) for over a year to help reduce shedding and improve the appearance of volume while improving hair health. As I personally had Long Covid and have thyroid disease, I know many others who are also looking to improve hair health from the hair loss that comes from these and many other medical conditions. I’ve been asked: Is Biotin good or bad for you and does Biotin affect thyroid – especially when used topically, like in Vegamour? While I am NOT a medical professional and cannot give medical advice, I have pulled together the information you need below to discuss it with your own health provider and make a decision about what’s right for you.

The bottom line up front: Biotin is an essential element of health, and supplementation has been shown to improve hair, nails and skin. Topical application can increase serum levels. The good: the body is absorbing it; the bad: it can alter hormone testing). All sources suggest simply stopping use of supplements (ingested or topical) 48-72 hours before testing, when the water soluble Biotin will leave the system.

First, why does Biotin help hair health?

Biotin, also known as vitamin B7, stimulates keratin production in hair and can increase the rate of follicle growth. It is not stored for long in the body – most of yours is from the foods you eat. In order to be effective, it needs to be consumed. [source]

I have only taken Biotin as it is available in whole food sources, including Paleo Valley’s Organ Complex. I prefer this to just a Biotin supplement because of these findings:

Consuming foods rich in healthy vitamins and minerals will help with overall hair health. The best natural sources of biotin are meat, eggs, fish, seeds, nuts, and vegetables. These will help fortify your hair follicle by boosting your keratin, according to the National Institutes of Health.

By making your hair stronger, it will be less prone to fall out. Adults should consume around 30 mcg/day, and women who are breastfeeding should increase their intake to 35 mcg/day with physician support and guidance. Foods containing Vitamin E such as avocado and nut butter can also support hair health. Lastly, ensure you’re getting enough omega-3 and omega-6 fatty acids through foods like fish, walnuts, and chia seeds. Most people benefit from supplementing with 2000mg a day of omega-3 fatty acids.

That said, Biotin can also be found topically, like products made for hair, lashes or brows. In addition to using Vegamour, I also use Beautycounter’s Think Big All-in-One Mascara – both of which have been shown in clinical trials to improve hair health.


  • Reduce signs of shedding by 76%
  • Increase the appearance of hair density by up to 52%

I personally use the Clarifying Serum, GRO Shampoo & Conditioner, and Dry Shampoo.

Think Big All-in-One Mascara

Immediate results:

  • 93% experienced fuller, thicker lashes
  • 93% experienced visibly longer, defined, and separated lashes

After just four weeks:

  • 97% experienced fuller and healthier-looking lashes
  • 93% experienced thicker-looking lashes


How Hair Loss Happens

Biotin deficiency can cause alopecia and a characteristic scaly, erythematous dermatitis around body orifices in infants, children, and adults. For adults, prolonged biotin deficiency can result in depression, lethargy, hallucinations, and paresthesias of the extremities. [source]

AGING: As we age, the anagen (growth) phase can shorten due to decreased levels of IGF-1 and microRNA31. Hair moves into the resting phase more quickly, causing excess shedding and thinning of hair. Also, as we age, our hormone levels change which often results in increased levels of dihydrotestosterone (DHT). DHT can damage the dermal papillae, resulting in inflammation, reduced circulation and follicle miniaturization.

STRESS & LACK OF SLEEP: Anxiety, fear and poor sleep can cause cortisol levels to spike. Increased cortisol levels can cause hair to prematurely exit the anagen phase and enter into the shedding phase. Cortisol can also trigger proinflammatory cytokines, increase interleukin 1, 6 levels and cause weight gain. I mean, if you’re running from a tiger, your body doesn’t need to prioritize hair growth. Our bodies can’t tell the difference between stress from tigers and taxes.

POOR NUTRITION: A diet low in zinc, iron, vitamin A, B6 & B12, C, D, E, biotin, folic acid and natural collagen boosters can also lead to hair thinning and loss.

‘DIRTY’ HAIR CARE PRODUCTS & ENVIRONMENTAL POLLUTION: Use of hair products containing synthetic chemicals, fragrances and silicones can damage & dehydrates hair while blocking pores, irritating the scalp and inhibiting healthy sebum production. Environmental pollution can also cause growth signals to weaken over time.

Does topical Biotin affect thyroid?

The short answer: Biotin is absorbed topically, but will exit your body within 2-3 days and not in significant enough volume to negatively affect hormone results. It has benefits to those suffering unhealthy symptoms of the hair, skin and nails that may be worth working with your medical professional to watch serum levels of Biotin being affected. [source]

While there are no known hazards of Biotin, and it is noted as essential to health, the American Thyroid Association (ATA) has recommended that patients stop taking biotin for at least 2 days before thyroid testing to avoid the risk of having a misleading test.

There are numerous reports of biotin interference with laboratory testing, specifically with thyroid function tests. Most commonly, biotin use can result in falsely high levels of T4 and T3 and falsely low levels of TSH, leading to either a wrong diagnosis of hyperthyroidism or that the thyroid hormone dose is too high. The ATA has recommended that patients stop taking biotin for at least 2 days before thyroid testing to avoid the risk of having a misleading test. [source]

The reason this is the case is because Biotin leaves the body quickly. Your doctor also can advise you on whether you should stop taking your supplement ahead of an upcoming lab test. Most water-soluble vitamins (like Biotin) flush out of your body in 24 to 48 hours, but it might take longer depending on the dose you’re taking. [source]

Why does Biotin affect thyroid levels?

This clinical trial supposes that it’s because “The biotin molecule is also sometimes used as part of the lab technology to measure hormone and protein levels in the blood. It is possible that high doses of ingested biotin may interfere with accurate hormone or protein measurement using biotin related in vitro measurement systems. Such interference, if present, could lead to misdiagnosis.”

In this case series,  ingestion of 20 mg or more of Biotin led to a potent and clinically relevant thyroid bioassay interference in all the four cases presented here. Clinicians should consider these findings in patients taking biotin supplements of any dose before ordering a thyroid function assay and when interpreting the results. Biotin should be discontinued for at least 48-72 hours.

In fact, this pending study is tracking this right now.

It is important to note that Biotin is used therapeutically in many positive uses, including autoimmune disorders. Definitely work with your medical professional to decide if supplementation, topical application, or simply increasing Vitamin B-rich foods could be right for you.

How can I tell if Biotin is in the products I use?

Biotin (or derivatives of) can also be called:

  • Biodermatin,
  • Biokur,
  • Biotin,
  • Gelfert (Biotin) or Biotin Gelfert,
  • Hermes (Biotin) or Biotin Hermes,
  • Biotin ratiopharm or Biotin-ratiopharm,
  • Biotine Roche Deacura or (Roche, Biotine)
  • Gabunat
  • Medebiotin
  • Rombellin
  • Vitamin H

It is in Vegamour, which combined with their vegan Keratin complex and CBD has been a HUGE game change for my hair health!

It is also in Think Big All-in-One Mascara, which has won performance awards for its clinical performance in improving lash health over time.


My layman’s non-medical-professional take, I would absolutely keep using these products that have shown to work well for me – and simply not use them 3 days prior to testing.


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