Biotin: What Is It and How Does It Work?

Published December 2nd, 2021 by Corey Riley
Fact Checked by
Erik Rivera
Medically Reviewed:
Camille Freking
Updated Date: Jun 27th, 2022

What is biotin | Benefits | Scientifically proven? | Symptoms of biotin deficiency | Side effects | Safety

Biotin is a water-soluble B vitamin that can help promote healthy hair, skin, and nails. It also helps to regulate blood sugar levels and could even help pregnant women.

But biotin's benefits don't stop there.

Read on for everything you need to know about biotin including what it does, how to take biotin, foods that contain biotin, biotin side effects, recommended daily dose of biotin, and more.

What is biotin?

Biotin is a water-soluble nutrient, which aids with biotin absorption, that acts as a coenzyme in the body.

It helps to metabolize fats and carbohydrates, which are used for energy production by cells throughout your body.

Biotin also plays an important role in cell growth, cell reproduction, fatty acid synthesis, gluconeogenesis, which is the production of glucose from non-carbohydrate sources, and energy production.

It is a very important vitamin for human requirements

Biotin, also known as vitamin H or vitamin B7, is a water-soluble vitamin that aids in cell growth and the release of energy from food.

It also helps to maintain healthy skin, nerves, blood sugar levels, and other functions.

You may be wondering how biotin affects you when you take it since biotin doesn't contain any calories or fat.

The answer is biotin helps your body absorb nutrients more efficiently so they are used by your cells better.

While the absorption of biotin occurs in the intestines after your stomach breaks down proteins using biotinidase.

After intestinal absorption, biotin is stored in small amounts within cells, so you don't actually need to take biotin every day.

What are the benefits of biotin?

Biotin is often used to improve skin and hair health. Some people even treat their fingernails with biotin.

It may also be taken by people who have a biotin deficiency or other conditions that cause biotin levels in the body to fall too low.

The following are the most common benefits of biotin.

Hair growth

It is thought that biotin can help with hair loss.

Biotin is a popular ingredient in hair supplements because biotin has been shown to reduce dry and brittle hair, increase the volume of hair growth, and improve the overall appearance of your locks.

Pregnancy support

Many women take biotin during pregnancy due to its ability to help prevent neural tube birth defects (NTDs) such as spina bifida in their unborn babies.

NTDs can cause permanent disabilities and even death if they aren't treated appropriately. Please consult a doctor before taking biotin during pregnancy. 

Healthy blood sugar levels

Biotin plays an important role in how your body metabolizes carbohydrates, which is why biotin may help you maintain healthy blood sugar levels. 

Skin and nails

Biotin is involved in the metabolism of amino acids, which are necessary for healthy hair, skin, and nails.

So just like with hair, biotin can help your brittle nails, or your skin from developing a rash due to biotin deficiency.

Biotin may be used to treat acne, psoriasis, seborrheic dermatitis, and other skin conditions.

One study found biotin may be more effective than benzoyl peroxide alone at treating acne.

Are any of these benefits scientifically proven?

There is no doubt that biotin plays a critical role in our body and may be used in prenatal development, which is the development of the fetus in the womb and to help with glucose levels for diabetes.

More rigorous studies and clinical trials need to be carried out by the scientific community to support the claims and produce sufficient evidence regarding the benefits to your hair, skin, and nails.

What are the symptoms of biotin deficiency?

Biotin deficiency is rare in people who eat a balanced diet.

However, biotin deficiency may be more likely to occur when you are on an extremely low calorie or restrictive eating plan, such as being a vegan, for prolonged periods of time due to the lack of biotin-rich foods like eggs and dairy products.

Symptoms of biotin deficiency include hair loss, brittle hair, scaly dermatitis around the eyes and nose, also called seborrheic dermatitis, dryness of mouth, lips, skin, fatigue, and nausea among other symptoms.

Are there any side effects to taking biotin?

There are no serious side effects associated with biotin. However, biotin may interact with some medications so you should talk to your doctor before taking biotin if you're already on medication.

You may also experience nausea or an upset stomach due to the effects of biotin.

If you overdose on biotin you may see a skin rash and you should stop taking any biotin supplements immediately and talk to your healthcare provider.

If you take too much biotin, this will lead to the excretion of biotin in your urine so the chances of an overdose are very unlikely.

Your health care professional can also run blood tests to see if you are receiving too much biotin as it will result in a decrease in insulin, low vitamin C and vitamin B6 levels, and high levels of blood sugar.

Is biotin safe for everyone?

Biotin is generally considered safe when taken by mouth in appropriate doses not exceeding the recommended dietary allowance (RDA).

The recommended daily intake of biotin supplementation is 30-100 micrograms for adolescents and adults. Infants will usually receive a dose of 5 micrograms while pregnant women will usually have doses of biotin of around 35 micrograms.

Some research says that high-dose biotin or doses up to 300 micrograms per day do not cause any side effects, but you should always check with your doctor before starting daily biotin supplementation.

What foods contain biotin?

Biotin is naturally present in many foods, including liver, egg yolks, raw egg whites, salmon, and avocado which are all great sources of biotin.

Here is a list of foods that contain biotin and the biotin content of food in each serving.

Source Amount (μg / 100 g)

Chicken liver 187

Beef liver 42

Eggs 21

Egg white 5.8

Egg yolk 27

Salmon, canned in water 5.9

Pork chop 4.5

Turkey breast 0.7

Tuna, white, canned 0.7

Peanuts, roasted 17.5

Sunflower seeds, roasted 7.8

Almonds, roasted 4.4

Sweet potato 1.5

Broccoli 0.9

Tomato 0.7

Strawberry 1.5

Avocado 1.0

Corn, canned 0.05

Cheese 1.4

Milk 0.1

Corn flakes cereal 0.1

Oatmeal 0.1

Bread 0.1

French fries 0.3

Wine 0.1

Beer 0.1

Potatoes, mashed 0.1

These are some of the most popular foods to contain biotin. It is recommended that the normal, daily dose a healthy adult who is not pregnant should ingest is 30 micrograms for their dietary intake.

If you have any questions about incorporating these foods into your diet or the levels of biotin necessary for your adequate intake we recommend that you talk to your doctor or nutritionist.

Those with biotin nutritional deficiencies may be required to take a dietary supplement. 

What other forms of biotin are available?

You can find biotin in many different forms, including oral biotin in capsules, tablets, as well as biotin liquid and biotin powder.

Here are some of the most common forms you will see biotin sold as:

  • Creams or lotions that contain biotin
  • Biotin shampoo
  • Tablets
  • Capsules
  • Liquid
  • Powder

These forms are available at your local health food store, pharmacy, or online.

How long until you see results when taking biotin?

It can take anywhere from two weeks to six months for your body to produce a response to biotin.

Everyone's biochemistry is different, so it will vary depending on the amount of biotin you are taking and in what form. Some people say they notice their hair growing faster or thicker after using biotin supplements consistently over the course of one month while others say that biotin was not effective at all.

If you are taking biotin for hair growth, we recommend giving it some time before deciding if biotin is right for you or not.


Biotin is a water-soluble B vitamin that can be very beneficial to your body. It is known to help people with diabetes, prenatal care for the fetus and mother, hair regrowth, improved skin, and promotes nail health by preventing brittle fingernails.

It should be noted that while there are some benefits, more research and scientific evidence is necessary to confirm the benefit for your skin, hair, and nails.

There may be very mild side effects such as nausea or a rash when taking biotin.

However, overdosing is very unlikely because any excess biotin leaves your body through urinary excretion.

There are numerous foods that contain biotin that we demonstrated with our list above and we recommend you check the USDA website for a full list.

Biotin is available at most pharmacies, health food shops, and online retailers and typically comes in the form of a pill, tablet, powder, or liquid although other forms are available to supplement your biotin intake.

The daily recommended intake of biotin for adults is 30 micrograms for any healthy adult who is not pregnant, while pregnant women are recommended to take 35 micrograms from food sources.

If you take a supplement, please talk to your doctor regarding your dose as it can also interfere with other medications.

Typically it takes a few months to see results in your hair or nails should you take biotin for them; nevertheless, it is unique for each individual. If you have any further questions please talk to your doctor, nutritionist, or medical provider for more information about meeting your biotin requirements.

References, Studies and Sources: 

National Institutes of Health 


Mayo Clinic 

Published December 2nd, 2021 by Corey Riley
Fact Checked by
Erik Rivera
Medically Reviewed:
Camille Freking
Updated Date: Jun 27th, 2022

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