Hair vitamins are sold everywhere. They promise faster hair growth and healthier and shinier hair. But did you know that some of them can actually do the opposite and cause hair loss?

Related: How to make your hair grow faster – the no BS guide
Related: What you need to know about the causes of hair loss​

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What do hair vitamins consist of?

Hair growth vitamins usually contain a mix of ingredients. You can buy them freely over the counter or online, without consulting a doctor.

What many people don’t know is that some of these ingredients can actually cause hair loss when taking too much of it. Or when your vitamin levels were high, to begin with.

Even worse, these ingredients often are the first ones on the ingredient lists of hair vitamins!

Let’s look at some of the most common ingredients in hair vitamins and find out which ones you better skip.


Biotin is probably the best-known hair vitamin. Almost anyone you’d ask about a supplement for healthy hair and nails would tell you to take some Biotin supplements.

The scientific research paints a different picture though.

In fact, a healthy person usually produces enough biotin themselves. No need to supplement it. Additionally, there are no studies showing any benefits of biotin supplementation in healthy humans. So unless you suffer from some rare illness, you can skip the biotin supplement completely.

The good news is that there are no known effects of Biotin on hair loss. So while you are probably wasting your money taking it, this ingredient should cause your hair to fall out.

Vitamin A

Vitamin A is another ingredient found in many hair vitamins.

It does play an important role for your hair follicles and all they do. But it’s not as easy as taking as much Vitamin A as possible.

In order for this nutrient to be beneficial, you need to have exactly the right levels of it in your body.

If you get too much Vitamin A, it will cause hair loss. Over time, you will also develop other very unpleasant symptoms.

As you can get enough Vitamin A from a healthy diet alone, it is definitely safer to skip the supplements. Unless a doctor tells you otherwise. Always listen to the professionals!


For some reason, Selenium is another ingredient that keeps popping up in hair vitamins. This was very surprising to me because Selenium is known for being toxic when it reaches a certain concentration in your body.

On the other hand, there is no proper research on humans about any positive effects of supplementing it.

So why is it in hair vitamins? I am not sure. What I do know is that one side effect of Selenium toxicity is hair loss.

And I definitely want to avoid that!

Vitamin E

Vitamin E is another of the ingredients in hair vitamins.

It is a strong antioxidant and seems to have positive effects on hair growth.

On the other hand, there is some evidence for the opposite effect when people take a high dosage of Vitamin E. The reason behind this is that oversupplementing Vitamin E leads to decreased thyroid hormone production. This again will have a bad effect on your hair.

Like with Vitamin A, you probably get enough Vitamin E through a healthy diet alone. If you don’t, you might have some fat malabsorption disorder and need to see a doctor about it.

If you want to make sure that your hair vitamin is not causing hair loss for you, stay away from high doses of Vitamin E!

So which hair vitamins should I take?

My conclusion to these findings is to avoid supplementing random things. Always keep in mind that the companies selling these supplements want to make a profit.

If you really feel your hair might suffer from vitamin deficiencies, get your blood checked by a doctor. They can tell you exactly what is missing and how you can fill up your vitamin reserves.

In any case, make sure you have a healthy, balanced diet and your hair will grow in a healthy way!

Related: Healthy hair diet: See the best foods for healthy hair!

Do you take hair vitamins for hair growth or thinning hair? You might want to double check the ingredient lists. Some of the common hair vitamins can actually, ironically cause hair loss.