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Biotin Benefits for Hair Growth, Stronger Nails and Beautiful Skin


Biotin benefits - Dr. Axe

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.

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, vitamin B7 — biotin — must be present in order to convert and use these macronutrients for bodily energy to carry out physical activities and for proper psychological functioning.

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

Is biotin for hair growth a real possibility? Vitamin B7/biotin is commonly added to hair and skin beauty products, although it’s believed to not be absorbed very well through the skin and actually must be ingested to be fully beneficial.

Biotin can be found in foods like organ meats, eggs, avocado, cauliflower, berries, fish, legumes and mushrooms.

Biotin Deficiency

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 common foods provide biotin
  3. Researchers believe our intestinal digestive bacteria have the ability to create some biotin on their own (1)

So what causes a biotin deficiency? Biotin 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; because of this, toxic levels (or biotin side effects) are very rare. However, this also means that you must ideally ingest small amounts of vitamin B7 almost daily to keep your body’s supply high enough. (2)

As explained in a key study on biotin by Dr. Janos Zempleni et al., three proteins are important for the proper amounts of biotin to be maintained in the body (a process called homeostasis).  These proteins are: biotinidase, the sodium-dependent multivitamin transporter (SMVT) and holocarboxylase synthetase (HCS). These proteins work together to make sure that biotin is released from foods that we eat and then absorbed through the gastrointestinal system. (3) Certain other proteins can sometimes interfere with this process, including avidin, which is found in raw egg whites.

Increased-risk factors for vitamin B7/biotin deficiency include the following: (4, 5)

  • 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

Although a biotin deficiency is very rare, when it does occur, symptoms can include:

  • dry, irritated skin
  • brittle hair or hair loss
  • lack or energy or chronic fatigue
  • digestive and intestinal tract issues
  • muscle aches and pains
  • nerve damage
  • mood changes
  • menstrual cramps
  • tingling in the limbs
  • cognitive impairments

Biotin Supplement Dosage and the RDA of ‘Vitamin B7’

According to the National Academy of Science’s Institute of Medicine, in order to receive biotin benefits, the daily recommended value of biotin is: (6)

  • 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 breast-feeding

Biotin vitamins or supplements are available over-the-counter in tablet or capsule forms, and you can also found liquid biotin online or in your local vitamin shop. Common biotin dosage ranges from 1,000 micrograms to 10,000 micrograms, which are much higher amounts than your daily recommended value. Some people choose to take biotin for hair growth and younger looking skin, and there’s some evidence to suggest that these biotin uses are beneficial. If you want to try biotin supplements, start with smaller doses and work your way up if you’re noticing positive changes.

Vitamin B7 can also be found as part of B-complex supplements, also sometimes called Adrenal Support Complex or Energy Complex supplements. These types of supplements usually include a full spectrum of B vitamins, including vitamin B6, vitamin B12, vitamin B2 riboflavin and vitamin B3 niacin.

Together, the B vitamin complex support metabolism activity, brain functions, nerve signaling and many other important daily functions. They also work with one another, so taking B vitamins together is always the best way to ensure you’ll get the most results.

If you plan to take B vitamin complex supplements, keep in mind that not all supplements 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. Acquiring vitamins like vitamin B7 in this natural way gives you the most biotin benefits and helps you avoid unwanted, ineffective, synthetic vitamin fillers and toxins.

Food Sources of Biotin (Vitamin B7)

There are actually eight different forms of biotin, but only one is naturally occurring — the kind found in food sources. This type is called “D-biotin” and is believed to be the only type that has full vitamin capabilities. This is another example of why it’s always best to get your vitamins and minerals from real food sources whenever possible, since they include nutrients just as nature intended for the body to use.

In 2004, when researchers examined 51 different foods to identify how much biotin was available, they found a wide range of varying biotin levels within each food. For those reasons, many authorities (including the USDA) do not list the amount of biotin available in common foods. However, according to studies, the foods below were some of the highest to be tested, although you will see the amount of biotin within each still ranges quite a bit.

Here are some of the 9 best food sources of biotin: (7)

  • Liver  — 3 ounces cooked: 27–35 milligrams
  • Eggs — 1 whole: 13–25 milligrams
  • Yeast — 7 grams/about 1 tablespoon: 1.4–14 milligrams
  • Salmon — 3 ounces: 4–5 milligrams
  • Cheese (try organic goat cheese) — 1 ounce: 0.4–2 milligrams
  • Avocado — 1 whole: 2-6 milligrams
  • Raspberries — 1 cup: 0.2–2 milligrams
  • Cauliflower — 1 cup: 0.2–2 milligrams
  • Whole Grain Bread (try Ezekiel bread) — 1 slice: 0.2–6 milligrams

Additionally, other berries, mushrooms and other types of fish are also thought to be good sources of biotin.

Interestingly, vitamin B7 is found exclusively in the yolk of the egg and is not at all present in egg whites. Some reports have shown that not only do people miss out on B vitamins when they only eat egg whites and discard the yolk, but that egg whites actually have the ability to deplete the effects of B vitamins, too — possibly even creating a vitamin B7 deficiency. (8)

Adding It to Your Diet

To get more biotin benefits from your diet naturally, try some of these recipe ideas that use foods rich in B vitamins:

Biotin benefits

7 Biotin Benefits and Uses

1. Supports a Healthy Metabolism

Biotin regulates gene expressions that are critical in carrying out functions of the metabolism. (9)

Vitamin B7, along with other B vitamins, is needed to convert the food you eat into useable energy that supports a healthy metabolism. Vitamin B7 does this in several ways: (10)

  • 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.

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, which is extremely beneficial in our society where cases of type 2 diabetes are so common.

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.

2. May Improve Glucose Intolerance and Help Balance Blood Sugar

Vitamin B7/ biotin, 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. (11) Better insulin response helps to reduce the risk of widely fluctuating blood sugar levels, which can lead to prediabetes, 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.

Does biotin make your hair grow? You may notice that this “hair vitamin” is included in many cosmetic face creams, hair masques and other over-the-counter beauty products, but it’s much more effective when it’s eaten, rather than applied topically, or taken as a supplement.

According to studies, taking high doses of biotin can 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. (12)

How much biotin for hair growth should you take? 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 for hair loss, you can start by taking one 1,000 micrograms biotin vitamin and increasing the amount of biotin foods you consume in a day.

Other biotin benefits include helping to protect skin from acne, fungal infections, rashes and severe dryness and cracking. (13, 14)

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. (15) 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 studies. Vitamin B7 has been shown to have positive results with increasing “good” HDL cholesterol, while helping to lower “bad” LDL cholesterol. 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. (16)

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.

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. (17)

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.

Possible Biotin Side Effects and Precautions

Overconsumption of vitamin B7 is not thought to be a threat and very few, if any, cases of vitamin B7 toxicity have been reported, so there’s not a high risk of biotin overdose. Vitamin B7 levels may be affected, however, 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.

No biotin 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.

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 in the body.

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 doctor advises you otherwise.

Read Next: Rosemary Oil Uses and Benefits for Hair Growth + More

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