Biotin Benefits for Hair, Skin and Health - Dr. Axe

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Biotin Benefits the Entire Body — Does that Include Your Hair?


Biotin benefits - Dr. Axe

Biotin acts as a coenzyme in the body that’s needed for the metabolism of fatty acids, amino acids and glucose. This means that when we eat foods that are sources of fats, proteins and carbohydrates, biotin — also called vitamin B7 — must be present in order to convert and use these macronutrients.

Our bodies then have the energy they need to carry out physical activities, for proper psychological functioning, and for growth.

Biotin benefits include helping to give us a young, attractive appearance since this vitamin plays a major part in maintaining the health of our hair, nails and skin. In fact, it sometimes gets the nickname the “H” vitamin. This stems from the German words Haar and Haut, which mean “hair and skin.”

Is biotin for hair growth a real possibility? Let’s examine.

What Is Biotin?

Biotin, or vitamin B7, is a water-soluble vitamin that’s a part of the vitamin B complex — a group of key nutrients needed for healthy metabolic, nerve, digestive and cardiovascular functions.

A vitamin B7/biotin deficiency is rare in nations where people generally consume enough calories and food in general. This is mainly because of three reasons:

  1. The recommended daily requirements are relatively low.
  2. Many biotin foods are commonly eaten.
  3. Researchers believe our intestinal digestive bacteria have the ability to create some biotin on their own.

Biotin Products

Biotin products have recently become a trend among consumers wishing to have longer, healthier hair and nails. If you’re looking to take a biotin supplement for this purpose or for other health improvements, you have several options, such as: biotin pills, biotin vitamins that include other B vitamins, skincare serums and lotions that contain biotin, and biotin shampoos.

Supplements are available over-the-counter in tablet or capsule forms, and you can also find liquid biotin online or in your local vitamin shop.

Vitamin B7 can also be found as part of B-complex supplements, which include a full spectrum of B vitamins, including vitamin B6vitamin B12vitamin B2 riboflavin and vitamin B3 niacin. Together, the B vitamin complex supports metabolism activity, brain functions, nerve signaling and many other important daily functions.

The vitamins also work with one another, so taking B vitamins together is always the best way to ensure you’ll get the most results.

Biotin for Hair Growth?

Thinning hair is one symptom that is tied to biotin deficiency but as explained above, such a deficiency is rare.

Also, vitamin B7 is commonly added to hair and skin beauty products, although it’s believed to not be absorbed very well through the skin. Some research suggests you get the most biotin benefits when it’s ingested from either food sources (such as B vitamin foods) or supplements.

What’s the best way to obtain biotin from your diet? By eating biotin-rich foods — things like organ meats, eggs, avocado, cauliflower, berries, fish, legumes and mushrooms.

Biotin benefits do appear to help build proteins needed to maintain youthful hair and skin, including keratin.

At least several studies, including one published in Dermatology Research and Practice and another in the Journal of Clinical and Aesthetic Dermatology, have found evidence that taking supplements daily that include biotin for about 3–6 months can help to promote hair growth and reduce hair loss/shedding. One of these studies found that compared to control-treated subjects, those taking the biotin-containing supplements perceived improvements in overall hair volume, scalp coverage and thickness of hair body after 90 days, and hair shine, skin moisture retention and skin smoothness after 180 days.

A 2017 review focused on the effectiveness of biotin for hair growth states that “we found 18 reported cases of biotin use for hair and nail changes. In all cases, patients receiving biotin supplementation had an underlying pathology for poor hair or nail growth. All cases showed evidence of clinical improvement after receiving biotin.”

That being said, according to the conclusion of the review, biotin supplementation may only really be effective if someone is deficient (which, again, is rare).


1. Supports a Healthy Metabolism

Biotin regulates gene expressions that are critical for carrying out functions of the metabolism. Vitamin B7, along with other B vitamins, is needed to convert the food you eat into useable energy that supports a healthy metabolism.

It does this in several ways:

  • It converts glucose from carbohydrates and sugar sources into useable “fuel” that is the body’s preferred source of energy.
  • It helps the body use amino acids from proteins to carry out multiple body functions.
  • It activates fatty acids from fat-containing foods like oils or animal fats.

Without enough vitamin B7 present in the body, symptoms of a sluggish metabolism may appear like low energy levels, fatigue, weight gain, digestive problems, possible development of diabetes, changes in appetite, poor moods and more.

Only once the body can use macronutrients from food for energy will normal, healthy metabolic activity take place. Vitamin B7 also improves the metabolism and utilization of glucose, offering some protection against insulin resistance/type 2 diabetes.

2. May Improve Glucose Intolerance and Help Balance Blood Sugar

Vitamin B7, especially when combined with chromium, has been shown to help lower blood sugar in people with diabetes. This is especially true for those who have blood glucose (sugar) levels that are not controlled well by prescription medicines.

Biotin benefits blood glucose levels because it facilitates the activity of insulin, which is the crucial hormone needed to bring blood sugar back to a balanced state. Better insulin response helps to reduce the risk of widely fluctuating blood sugar levels, which can lead to prediabetes symptoms, type 2 diabetes, weight gain and forms of metabolic syndrome.

Biotin decreases the expression of enzymes that stimulate glucose production by the liver, therefore less sugar is released into the bloodstream. For this reason, vitamin B7 deficiency has been linked to impaired glucose tolerance and decreased utilization of glucose, which are risk factors for diabetes.

Vitamin B7 can also help reduce symptoms of existing cases of diabetes, including nerve pain.

3. Maintains Healthy Hair, Skin and Nails

Vitamin B7 is needed to maintain healthy skin, hair and nails, so when someone experiences a vitamin B7 deficiency, symptoms may manifest in the form of thinning, splitting and brittle hair, or dermatitis that results in dry, irritated skin.

How does biotin help hair growth? Taking a biotin supplement (or “vitamin for hair growth,” as some supplements may be marketed) can help to reverse deficiency in this vitamin and support production of proteins and enzymes that are needed for hair growth.

Biotin benefits hair since it’s been shown to help decrease alopecia (hair loss) in adults and to improve protein synthesis and the infrastructure of keratin, which is a protein that makes up hair, skin and nails. Keep in mind that research shows deficiency in other nutrients, such as zinc, selenium and iron may also contribute to thinning hair, not to mention that many health conditions such as hormonal imbalances/endocrine disorders may be to blame.

According to studies, taking high doses of biotin can also help treat weak hair and brittle nails. In fact, this benefit of vitamin B7 was first discovered when horses were effectively treated with biotin to correct problems with the horses’ hoofs becoming brittle and cracked.

Other biotin benefits include helping to protect skin from acne, fungal infections, rashes and severe dryness and cracking.

Something important to note is that although biotin is included in many cosmetic face creams, hair masques and other over-the-counter beauty products, it appears to be much more effective when it’s ingested/eaten, rather than applied topically.

4. Protects Brain Function and Fights Cognitive Decline

Biotin benefits the health of the nervous system because of its role in nerve signaling and neurotransmitter activity. B vitamins together influence memory function and defend against age-related cognitive impairment, such as neurodegenerative disorders like Alzheimer’s disease or dementia.

Because of their role in synthesizing hormones that are related to a mood regulation, B vitamins like vitamin B7 help to keep up a positive mindset, boost energy and increase concentration.

5. Helps Maintain a Healthy Cardiovascular System

B vitamins like vitamin B7 play a part in defending against common causes of heart disease including inflammation, atherosclerosis (or plaque build-up in the arteries), heart attacks and stroke.

Vitamin B7 and chromium together can help improve cholesterol levels, according to some studies. Vitamin B7 has been shown to have positive results with increasing “good” HDL cholesterol, while helping to lower “bad” LDL cholesterol and triglyceride levels.

This is especially true in people with diabetes who are susceptible to heart disease.

6. Supports Thyroid and Adrenal Function

B vitamins like vitamin B7/biotin are needed for proper thyroid activity and defending against adrenal fatigue. The thyroid plant and adrenal gland are “master” glands that are responsible for multiple body states, including hunger, sleep, pain perception, mood and energy.

A deficiency in B vitamins can result in thyroid and adrenal complications — and thus create many negative symptoms, such as fatigue, weight gain or loss, trouble sleeping, and more.

That being said, there’s evidence that taking very high doses of biotin can lead to incorrect results on various thyroid/endocrine laboratory tests, so working with your doctor if you have a history of thyroid dysfunction is important.

7. Needed to Build and Repair Tissues and Muscles

Biotin benefits include helping the growth and maintenance of bodily tissues, including to help repair and build muscles. When tissue or muscle is broken down, B vitamins like vitamin B7 biotin work to build back the strength of muscle and tissue that leads to growth.

B vitamins also help reduce inflammation that can result in muscle or joint aches, pains, or trouble moving. Even more seriously, a deficiency in vitamin B7 and other B vitamins can stunt growth and result in improper development in fetuses and infants.

This is one reason why acquiring enough vitamin B7/ biotin and all other B vitamins is crucial during pregnancy.

Biotin benefits

Biotin Deficiency

As explained above, biotin deficiencies are rare but can occur. Having dry, irritated skin, brittle hair or hair loss, a lack or energy or chronic fatigue, or going digestive and intestinal tract issues can all be signs that you may not be getting enough biotin.

According to an article that appeared in the American Journal of Clinical Nutrition, some underlying causes of biotin deficiency include:

  • pregnancy
  • long-term use of certain anti-seizure medications
  • excessive alcohol use
  • consuming lots of raw egg whites
  • smoking
  • prolonged antibiotic use
  • intestinal malabsorption issues or serious digestive disorders like Crohn’s disease, celiac disease or leaky gut syndrome

Drug interactions can also lower biotin levels in the body. Certain medications — including the skin medication isotretinoin (Accutane) that is prescribed for acne — may reduce the activity of vitamin B7. Abnormally high doses of other B vitamins like pantothenic acid can also lower levels of vitamin B7 biotin.

Vitamin B7 levels may also be affected if someone is taking anti-seizure medications or oral antibiotics, or if they have a known digestive disorder that can disrupt normal intestinal bacteria levels.

Supplement Dosage

Most healthy adults meet biotin requirements through a well-balanced diet. Keep in mind that in supplement form, common biotin dosages range from 1,000 micrograms to 10,000 micrograms, which is much higher than your daily recommended value, or the amount considered to be an “adequate intake.”

“Recommended daily allowances” (RDAs or RDIs) of biotin have not been established due to a lack of sufficient evidence. According to the National Institutes of Health, the “Adequate Intake” (the level that is assumed to ensure nutritional adequacy) to obtain biotin benefits for different age groups is as follows:

  • 5 micrograms daily for infants
  • 6–8 micrograms daily for infants ages 7 months to 3 years old
  • 12–20 micrograms daily for children ages 4–13 years old
  • 25 micrograms for adolescents
  • 30 micrograms for male and female adults over 19 years old
  • 30 milligrams for pregnant women and 35 milligrams for women who are breastfeeding

How much biotin should you take for hair growth? The proper dosage depends on a few factors, including your age and whether or not you have a biotin deficiency.

When it comes to using biotin benefits for hair loss/to promote growth, you can start by taking 1,0000 mcg of biotin daily and increasing the amount of biotin foods you consume in a day. A general recommendation is try working your way up to taking about 2.5 to 3 mg (or 2,500 to 3,000 mcg) daily, which will cover your needs and then some.

If you want to try biotin supplements, start with smaller doses and work your way up if you’re noticing positive changes. Keep in mind that not all types are created equal.

To get the most biotin benefits, purchase a high-quality multivitamin or supplement product that is made from real food sources and doesn’t contain fillers or toxins in order to get the most benefits. These are made by joining together different collaborative nutrients so your body recognizes the vitamins and minerals and can use them in a synergistic way — similar to how they appear in food sources.

Risks and Side Effects

Are there side effects to taking biotin? Biotin side effects for rare because this vitamin (like other B vitamins) is water-soluble, which means it travels in the bloodstream and any excess or unused quantities present in the body are eliminated through urine.

Therefore, the body doesn’t build up reserves of biotin, and it’s very difficult to consume too much or to reach toxic levels.

Very few side effects have been reported when taking doses that are less than 10 milligrams per day. So taking biotin pills or supplements is considered safe when the dosage is within the recommended amounts.

That being said, it’s possible to experience minor adverse reactions like indigestion, nausea, cramping or diarrhea. And if someone were to take a very high dose for an extended period of time, they may possibly develop biotin overdose symptoms like skin rashes, lower vitamin C and B6 levels, and high blood sugar levels.

The bottom line? True of all B vitamins, very high doses of vitamins from supplements can impact doses of others, so it’s always advised to only take the recommended dose, unless your healthcare professional advises you otherwise.

Final Thoughts

  • Biotin, also called vitamin B7, is a water-soluble vitamin that’s a part of the vitamin B complex — a group of key nutrients needed for healthy metabolic, nerve, digestive and cardiovascular functions.
  • Biotin benefits include supporting your metabolism, glucose tolerance, heart health, muscles and tissues, and skin and hair health.
  • Does taking it for hair growth work? This vitamin has been shown in limited studies to help decrease alopecia (hair loss) in adults and to improve protein synthesis and the infrastructure of keratin, which is a protein that makes up hair, skin and nails, among other biotin benefits.
  • Deficiency in vitamin B7 is rare because it’s found in many commonly eaten foods such as meat, fish, cheese, legumes, nuts, eggs, etc. In supplement form, dosage recommendations range from about 1 mg to 3 mg (or 1,000 to 3,000 mcg) daily, which will cover your daily needs and then some.
  • What are the side effects? Side effects are rare, but when taken in very high doses may include indigestion, skin rashes, lower vitamin C and B6 levels, and high blood sugar levels.

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