8 Biotin (Vitamin B7) Health Benefits + Side Effects, Dosage

Biotin – Vitamin B7

8 Biotin (Vitamin B7) Health Benefits + Side Effects, Dosage

You may recognize vitamin B7 by its popular name of biotin. It is a water-soluble B vitamin found naturally in some foods and also in supplements. Biotin plays a vital role in assisting enzymes to break down fats, carbohydrates, and proteins in food. It also helps to regulate signals sent by cells and the activity of genes. [1]

An RDA (Recommended Dietary Allowance) does not exist for biotin because there is not enough evidence to suggest a daily amount needed by most healthy people. Instead, there is an AI (Adequate Intake) level, which is assumed to ensure nutritional adequacy.

AI: The AI for biotin for men and women 19 years and older and for pregnant women is 30 micrograms daily. Lactating women need 35 micrograms daily.

UL: A Tolerable Upper Intake Level (UL) is the maximum daily dose unly to cause adverse side effects in the general population. There is no UL for biotin due to a lack of reports showing negative effects from very high intakes.

Vitamin B7 and Health

Biotin supplements are often glamorized as a treatment for hair loss and to promote healthy hair, skin, and nails. Although a deficiency of biotin can certainly lead to hair loss and skin or nail problems, evidence showing a benefit of supplementation is inconclusive. A handful of case reports and small trials have shown a benefit, but the study designs had weaknesses:

  • The diagnoses of the type of hair conditions varied or were not cited at all. Researchers have also noted that certain hair loss conditions alopecia can resolve spontaneously without treatment, so it is not clear that biotin supplements specifically caused the regrowth. [2]
  • The studies did not measure the participants’ baseline blood levels of biotin to see if they were normal or deficient. Some research suggests that biotin supplements may be of most benefit in people who have a deficiency of the nutrient; however, again, there is a lack of studies that have measured biotin levels before and during supplementation to confirm this conclusion. [3,4]
  • To date, there is a lack of published studies to suggest that biotin supplements are beneficial for the growth of normal, healthy hair and nails. [2,5]

In November 2017, the U.S. Food and Drug Administration (FDA) issued a warning reports of biotin supplements interfering with laboratory blood tests, causing incorrect results.

High doses have produced either falsely elevated or decreased blood levels, depending on the test. This has affected lab results of certain hormones, such as thyroid-stimulating hormone and vitamin D, as well as a biomarker for heart attacks called troponin.

[6] Case reports of this occurrence showed people taking biotin amounts much higher than the AI level (30 micrograms daily or 0.03 mg) but in doses commonly found in supplements (10-300 mg). Biotin is often added to multivitamins and hair/nail/skin supplements.

The FDA recommends that people inform their doctors at each visit of all supplements and doses they are taking.

Food Sources

  • Beef liver
  • Eggs (cooked)
  • Salmon
  • Avocados
  • Pork
  • Sweet potato
  • Nuts, seeds


A biotin deficiency in the U.S. is rare, as most people eat enough biotin in a varied diet.

Alcoholism can increase the risk of biotin deficiency and many other nutrients as alcohol can block their absorption, and also because alcohol abuse is generally associated with a poor dietary intake.

About a third of pregnant women show a mild biotin deficiency despite eating adequate intakes, though the exact reason is not clear. [1]

Symptoms appearing with a biotin deficiency:

  • Thinning hair
  • Scaly skin rashes around eyes, nose, mouth
  • Brittle nails


No evidence in humans has shown a toxicity of biotin even with high intakes. Because it is water-soluble, any excess amount will leave through the urine. There is no established upper limit or toxic level for biotin.

Did You Know?

Those who frequently enjoy raw eggs in recipes for mayonnaise, Caesar dressing, or eggnog may want to reconsider. A protein in raw eggs called avidin can bind to biotin, preventing its absorption. Cooked eggs are not an issue because avidin is broken down when heated.

B Vitamins
Vitamins and Minerals

  1. National Institutes of Health; Office of Dietary Supplements. Biotin: Fact Sheet for Health Professionals. https://ods.od.nih.gov/factsheets/Biotin-HealthProfessional/. Accessed 6/10/19.
  2. Walth CB, Wessman LL, Wipf A, Carina A, Hordinsky MK, Farah RS. Response to: “Rethinking biotin therapy for hair, nail, and skin disorders”. Journal of the American Academy of Dermatology. 2018 Dec 1;79(6):e121-4.
  3. Lipner SR. Rethinking biotin therapy for hair, nail, and skin disorders. Journal of the American Academy of Dermatology. 2018 Jun 1;78(6):1236-8.
  4. Lipner S. Reply to:“Response to ‘Rethinking biotin therapy for hair, nail, and skin disorders’”. Journal of the American Academy of Dermatology. 2018 Dec 1;79(6).
  5. Patel DP, Swink SM, Castelo-Soccio L. A review of the use of biotin for hair loss. Skin appendage disorders. 2017;3(3):166-9.
  6. S. Food and Drug Administration. The FDA Warns that Biotin May Interfere with Lab Tests: FDA Safety Communication. https://www.fda.gov/medical-devices/safety-communications/fda-warns-biotin-may-interfere-lab-tests-fda-safety-communication Accessed June 10, 2019.

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Source: https://www.hsph.harvard.edu/nutritionsource/biotin-vitamin-b7/

Biotin: Benefits, sources, and safety

8 Biotin (Vitamin B7) Health Benefits + Side Effects, Dosage
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Biotin is one of the B-vitamins, also known as vitamin B7.

It was once called coenzyme R and vitamin H. The H stands for Haar und Haut, which is German for hair and skin.

Biotin is water-soluble, which means the body doesn’t store it. It has many important functions in the body.

It’s necessary for the function of several enzymes known as carboxylases. These biotin-containing enzymes participate in important metabolic pathways, such as the production of glucose and fatty acids.

A commonly recommended intake is 5 mcg (micrograms) per day in infants and 30 mcg in adults. This goes up to 35 mcg per day in breastfeeding women.

Biotin deficiency is fairly rare. However, some groups such as pregnant women – may experience it in mild forms.

Eating raw eggs may also cause a deficiency, but you would need to eat a lot of eggs for a very long time. Raw egg whites contain a protein called avidin, which binds to biotin and prevents its absorption. Avidin is inactivated during cooking.

Summary: Biotin is a water-soluble B-vitamin that’s important for energy metabolism. Deficiency is quite rare, although it has been associated with the long-term consumption of raw eggs.

Biotin has a range of possible benefits

1. Macronutrient metabolism

Biotin is important for energy production. For example, several enzymes need it to function properly.

These enzymes are involved in carb, fat and protein metabolism. They initiate critical steps in the metabolic processes of these nutrients.

Biotin plays a role in:

  • Gluconeogenesis: This metabolic pathway enables glucose production from sources other than carbs, such as amino acids. Biotin-containing enzymes help initiate this process.
  • Fatty acid synthesis: Biotin assists enzymes that activate reactions important for the production of fatty acids.
  • The breakdown of amino acids: Biotin-containing enzymes are involved in the metabolism of several important amino acids, including leucine.

Summary: Biotin assists in energy production. It supports a number of enzymes involved in the metabolism of carbs, fats, and protein.

2. Brittle Nails

Brittle nails are weak and easily become chipped, split or cracked.

It’s a common condition, estimated to affect around 20 percent of the world’s population.

Biotin may benefit brittle nails (7).

In one study, 8 people with brittle nails were given 2.5 mg of biotin per day for 6 to 15 months. Nail thickness improved by 25% in all 8 participants. Nail splitting was also reduced (8).

Another study of 35 people with brittle nails found 2.5 mg of biotin per day for 1.5 to 7 months improved symptoms in 67% of participants (9).

However, these studies were small and more research is needed.

Summary: Brittle nails are fragile and easily become split or cracked. Biotin supplements may help strengthen the nails.

3. Hair health

Biotin is often associated with increased hair growth and healthier, stronger hair.

There is very little evidence to support this.

However, a deficiency in biotin may lead to hair loss, which indicates that the vitamin is important for hair (2, 10).

While it is often marketed as an alternative treatment for hair loss, only people with an actual biotin deficiency get significant benefit from supplementing (11).

It is recommended that people with biotin deficiency take 30 to 100 micrograms (mcg) per day. Infants would need a smaller dose of 10 to 30 mcg.

Whether it improves hair growth in healthy people has yet to be determined.

Summary: Biotin is claimed to promote hair growth and healthy hair, but the evidence is weak. However, deficiency has been linked to hair loss, and those who are actually deficient may benefit from supplementing.

4. Pregnancy and breastfeeding

Biotin is important during pregnancy and breastfeeding. These life stages have been associated with an increased requirement for this vitamin (12, 13).

In fact, it has been estimated that up to 50% of pregnant women may develop a mild biotin deficiency. This means that it may start to affect their well-being slightly, but isn’t severe enough to cause noticeable symptoms (14, 15, 16).

Deficiencies are thought to occur due to the faster biotin breakdown within the body during pregnancy (17).

Additionally, a major cause for concern is that animal studies have found that a biotin deficiency during pregnancy may cause birth defects (18, 19, 20).

Nevertheless, remember to always consult your doctor or dietitian/nutritionist before taking supplements during pregnancy and while breastfeeding.

Summary: If you’re pregnant or breastfeeding, your biotin requirements may go up. Up to 50% of women may get less of this vitamin than they need during pregnancy.

5. Reduced blood sugar in people with diabetes

Type 2 diabetes is a metabolic disease. It’s characterized by high blood sugar levels and impaired insulin function.

Researchers have studied how biotin supplements affect blood sugar levels in type 2 diabetics.

Some evidence shows biotin concentrations in blood may be lower in people with diabetes, compared to healthy individuals (21).

Studies in diabetics given biotin alone have provided mixed results (21, 22).

However, several controlled studies indicate that biotin supplements, combined with the mineral chromium, may lower blood sugar levels in some people with type 2 diabetes (23, 24, 25, 26).

Summary: When combined with chromium, biotin may help lower blood sugar levels in people with type 2 diabetes.

6. Skin health

Biotin’s role in skin health isn’t well understood. However, it is known that you may get red, scaly skin rashes if you’re deficient (27, 28).

Some studies also suggest that biotin deficiency may sometimes cause a skin disorder called seborrheic dermatitis, also known as cradle cap (29, 30).

Biotin’s role in skin health may be related to its effect on fat metabolism, which is important for the skin and may be impaired when biotin is lacking (27).

There is no evidence showing that biotin improves skin health in people who aren’t deficient in the vitamin.

Summary: People with a biotin deficiency may experience skin problems. However, there is no evidence that the vitamin has benefits for skin in people who aren’t deficient.

7. Multiple sclerosis

Multiple sclerosis (MS) is an autoimmune disease. In MS, the protective covering of nerve fibers in the brain, spinal cord and eyes is damaged or destroyed (31).

This protective sheath is called myelin, and biotin is thought to be an important factor in producing it (32).

A pilot study in 23 people with progressive MS tested the use of high doses of biotin. Over 90% of participants had some degree of clinical improvement (33).

While this finding needs much more study, at least two randomized controlled trials have been carried out in people with progressive MS. The final results have not been published, but the preliminary results are promising (34, 35, 36).

Summary: High biotin doses hold promise for treating multiple sclerosis, a serious disease that affects the central nervous system.

Biotin is found in a wide variety of foods, so an actual deficiency is rare.

Foods that are particularly good sources include:

  • Organ meats, such as liver and kidney
  • Yeast
  • Egg yolks
  • Cheese
  • Legumes, such as soybeans and peanuts
  • Leafy greens
  • Cauliflower
  • Mushrooms
  • Nuts and nut butters

In addition, your gut bacteria produce some amount of biotin. It’s also available as a supplement, either on its own or as a component of mixed vitamin supplements.

Summary: Many foods contain significant amounts of biotin, and it is also available as a supplement. Your gut bacteria can also produce it.

Biotin is considered very safe. Even mega doses of up to 300 milligrams (mg) daily to treat multiple sclerosis have not led to adverse side effects (33).

To put this in perspective, 300 milligrams is 10,000 times the commonly recommended 30 microgram dose for adults.

Because it’s a water-soluble vitamin, excess amounts are excreted in urine.

However, there have been some reports of high-dose biotin causing strange results on thyroid tests, so check with a doctor before using if you are currently taking thyroid medication (37).

Summary: Biotin appears very safe, even at extremely high doses. There are no known side effects of supplementing with biotin.

Biotin is a B-vitamin that plays a crucial role in carb, fat and protein metabolism.

Many of its potential health benefits are weak evidence. Nonetheless, it may be important for your skin, hair and nails.

Additionally, pregnant or breastfeeding women may require more biotin. High doses are also being investigated as a potential treatment for multiple sclerosis.

You can find biotin in a wide variety of foods, so actual deficiency is very rare.

For this reason, supplements probably have no significant benefits for healthy people who eat a balanced diet real food.

Source: https://www.medicalnewstoday.com/articles/318724

8 Biotin (Vitamin B7) Health Benefits + Side Effects, Dosage

8 Biotin (Vitamin B7) Health Benefits + Side Effects, Dosage

Vitamin B7, more commonly known as biotin, is a B vitamin. all B-type vitamins, biotin aids the body in breaking down carbohydrates, fats, and proteins for energy production. It also has roles in maintaining healthy skin, hair, and nervous system function.

Read this post to learn more about the potential health benefits of biotin.

What Is Biotin (Vitamin B7)?

Biotin, also known as vitamin B7, is a water-soluble B-complex vitamin essential for the growth and development of all organisms [1].

As a coenzyme of carboxylase enzymes, vitamin B7 is involved in the metabolism of fatty acids, amino acids, and carbohydrates [2].

Biotin has been shown to be important for many health factors including supporting neurological functions, steadying blood sugar levels, DNA stability, and hair, skin and nail health [3, 4].

The body cannot synthesize vitamin B7, so it needs to be obtained regularly from the diet and intestinal bacteria [5].

Biotin can be found in a wide variety of foods including animal liver, egg yolks, cow milk, and some fruits and vegetables [6].

Although vitamin B7 deficiency is rare, it can be dangerous if left untreated. Suboptimal levels or marginal deficiencies, which are a lot more common, have been linked to a variety of negative health effects including growth retardation, neurological dysfunction, hair loss, skin rash, muscle pain, and anemia [1].

Groups at risk for biotin deficiency include smokers, alcoholics, pregnant women, and people with inflammatory bowel disease (IBD) [7, 8, 9, 10].


Oral vitamin B7 supplements are completely absorbed even at high pharmacological doses (81.9 micromoles taken orally or 18.4 micromoles taken intravenously) [11].

Biotin is absorbed via a sodium-dependent multivitamin transporter (SMVT) in the small and large intestines [5].

After transport from the intestines into the systemic circulation, biotin is taken up by the liver and eventually crosses the blood-brain barrier into the central nervous system [12].

Soon after oral ingestion by humans, single high doses of biotin (600 micrograms and 900 micrograms) are eliminated from the circulation leading to a significant increase of urinary excretion. Therefore, for prolonged maintenance of blood biotin levels, lower doses (300 micrograms) each day for a week are recommended [13].

Roughly half of the absorbed vitamin B7 undergoes metabolism to bisnorbiotin and biotin sulfoxide prior to excretion. Vitamin B7, bisnorbiotin, and biotin sulfoxide are present in molar ratios of approximately 3:2:1 in human urine and blood [14].

The elimination half-life time of biotin is approximately 1 hour, 50 minutes [13].

Effective for:

Biotin is a coenzyme for carboxylases, the enzymes that assist in the metabolism of fats, proteins, and carbohydrates for energy production [15].

These enzymes are essential for the following processes:

  • Gluconeogenesis, the metabolic pathway that produces glucose from non-carbohydrate sources including amino acids [16].
  • Cellular energy production [17].
  • The use of branched-chain amino acids (e.g., leucine, isoleucine, and valine) for neurotransmitter production and energy [18].
  • Synthesis and breakdown of fatty acids for energy [19].
  • Insulin release [17].

Inadequate vitamin B7 levels in the body can slow down metabolism, which may lead to fatigue, digestive problems, and weight gain [1].

2) Brain Function

Biotin is required for myelin sheath formation, a fatty substance that surrounds nerves and facilitates nerve impulse conduction. As such, biotin deficiency can delay myelination [20].

Biotin deficiency can also lead to a number of other neurological symptoms, including seizures, lack of muscle coordination, learning disabilities, hallucinations, depression, and lethargy. Most of these conditions can be resolved with biotin supplementation [21, 22, 20].

High-dose biotin supplementation (5-10 mg/kg/day) was also effective in treating biotin-responsive basal ganglia disease, a rare brain metabolic condition characterized by seizures, confusion, and abnormal coordination, in a review of 18 cases [23].

Multiple sclerosis is an autoimmune disorder characterized by myelin damage and loss. Given its role in fatty acid synthesis and energy production (both are needed for myelin repair and axonal survival), it has been proposed that biotin may be effective in limiting or reversing multiple sclerosis-related impairments [24].

In fact, 2 clinical trials on 177 people found that high-dose vitamin B7 treatment was able to reverse disease progression and improve symptoms in patients with progressive multiple sclerosis. However, the treatment had little or no effectiveness at improving visual acuity in another trial on 93 people with multiple sclerosis [25, 26, 27].

3) Immune System Function

Vitamin B7 is needed for white blood cell development and its deficiency is linked to impaired immune function and an increased risk of infection [28, 29].

It increases the production of Th1 cytokines IL-1β and IFN-γ, which are essential for eliciting an immune response to fight bacterial and viral infections [30].

Inadequate levels of vitamin B7 are associated with decreased antibody synthesis, T cell decay, and lower amounts of spleen cells and T cells in both animals and humans [31, 29, 32].

Decreased rates of cellular proliferation during biotin deficiency may account for some of these adverse effects on immune function [33].

A deficiency of biotinidase, an enzyme that helps recycle biotin, is associated with chronic vaginal candidiasis and is treatable with biotin supplementation. Since 1 in every 123 people is believed to be biotinidase-deficient, women with chronic vaginal candidiasis may be responsive to biotin treatment [34].

1) Type 2 Diabetes

Biotin may help lower blood sugar levels by increasing insulin production, enhancing glucose uptake in muscle cells, and stimulating glucokinase, an enzyme in the liver that promotes glycogen synthesis [35, 36, 37].

Daily supplementation of vitamin B7 decreased fasting blood sugar concentrations by an average of approximately 45% in a clinical trial on 43 people with type 2 diabetes [38].

This vitamin increased the activity of 3 enzymes involved in glucose breakdown (pyruvate carboxylase, acetyl-CoA carboxylase, and propionyl-CoA carboxylase) in a clinical trial on 30 people [39].

Its combination with chromium picolinate improved blood sugar management in 2 clinical trials on almost 500 uncontrolled diabetics [40, 41].

Furthermore, high doses improved the symptoms of a nerve damage condition commonly exhibited in diabetic patients (diabetic neuropathy) [42].

All in all, the evidence suggests that supplementation with biotin, especially in combination with chromium picolinate, may help control blood sugar levels and reduce the risk of diabetic neuropathy.

You may use biotin as a complementary approach to managing your blood sugar levels if your doctor determines that it may be helpful in your case.

Never take biotin in place of the antidiabetic medication prescribed by your doctor.

2) Lowering the Risk of Heart Disease

Biotin is required for normal fat metabolism, which is critical for maintaining heart and blood vessel health [43, 44, 45].

In combination with chromium picolinate, vitamin B7 helped reduce heart disease risk factors by increasing high-density lipoprotein (HDL) levels and decreasing low-density lipoprotein (LDL) levels, especially in 2 clinical trials on almost 400 diabetic patients with heart disease [46, 47].

Pharmacological doses of biotin (15,000 mcg/day) were also effective in lowering blood triglyceride concentrations in 33 patients with elevated triglyceride levels [48].

Although limited, the evidence suggests that biotin may help reduce the risk of heart disease. You may discuss with your doctor if it may be recommendable in your case.

3) Skin, Hair, and Nail Health

Biotin deficiency is linked to a number of skin conditions, including seborrheic dermatitis (cradle cap) and eczema [49, 50].

This may be related to biotin’s roles in fatty acid synthesis and metabolism, which is critical for skin health [50].

Skin cells are particularly dependent on fat production since they require extra protection against damage and water loss from constant outdoor exposure [51].

Inadequate levels of vitamin B7 can also lead to hair loss, which is reversible with supplementation. Although some studies have found that vitamin B7 promotes hair growth in women with thinning hair, there is minimal evidence to support that it promotes hair growth in otherwise healthy individuals [17, 52, 53, 54].

Biotin may enhance the quality of brittle nails, with affected patients exhibiting firmer, harder, and thicker nails after treatment [55, 56, 57].

Again, the evidence is limited but suggests that biotin may improve hair, skin, and nail health. Discuss with your doctor if you can obtain any of these benefits by supplementing with biotin.

1) Preventing Birth Defects

Marginal biotin deficiency is common during pregnancy due to the increased biotin demands from the growing fetus [58].

In animals, even a subclinical level of biotin deficiency can result in cleft palate and limb abnormalities [59].

It is hypothesized that a low biotin status during pregnancy may increase the risk of birth defects in humans by altering fat metabolism and increasing genomic instability, both of which can lead to the development of chromosomal abnormalities and fetal malformations [60, 61].

In human embryonic palatal (roof of the mouth) stem cells, vitamin B7 depletion was found to suppress carboxylase production and cellular proliferation, indicating that lower levels of vitamin B7 may delay or halt the growth of the embryonic palate, resulting in cleft palate development [61].

However, definitive evidence establishing the connection between biotin deficiency in humans and the development of birth defects is currently lacking and thus, more research is required [62].

2) Preventing DNA Damage

Biotin covalently binds to histones, DNA binding proteins that help fold and package DNA into chromatin. The addition of biotin to histones plays a significant role in cellular proliferation, gene silencing, and DNA repair and stability [63, 17, 1].

Low levels of biotin can lead to inadequate histone biotinylation, which may result in genomic instability and abnormal gene expression (cellular production) and thus increases the risks of cancer. These effects have been shown to increase cancer risk in fruit flies and cell-based studies [64, 65, 66].

However, higher levels of biotin (up to 600 micrograms) were actually found to increase genomic instability and damage in 1 study in humans. This suggests that biotin’s DNA stabilizing effects may be dose-dependent [67].

In any case, the causal link between histone biotinylation and DNA damage risk in humans remains to be investigated [68].

Inflammatory and Allergic Disorders

Research from mouse models and human white blood cells indicates that biotin deficiency may increase the production of proinflammatory cytokines and aggravate inflammatory conditions [69, 70].

In biotin-deficient mice with nickel allergies, biotin supplementation decreased the production of pro-inflammatory cytokines and improved allergic inflammation, suggesting a potential therapeutic effect of biotin against inflammatory and allergic diseases in humans [69].

This may be a result of decreased NF-κB activity, which is activated during vitamin B7 deficiency [71, 72].

BTD Gene – The Enzyme that Recycles Biotin

The BTD gene encodes biotinidase, an enzyme that recycles biotin. Biotinidase transports free biotin through the bloodstream and attaches biotin to other proteins [73].

Single nucleotide polymorphisms (SNPs) in the BTD genome include the following:

SLC5A6 Gene – The Transporter that Transport Biotin Into the Cells

The SLC5A6 gene encodes the sodium-dependent multivitamin transporter that helps transport biotin into cells [76].

HLCS Gene – The Enzyme that Attaches Biotin to Other Proteins

This gene encodes holocarboxylase synthetase (HLCS), an enzyme that attaches biotin molecules to histones and carboxylase enzymes.

Mutations in this gene can reduce biotin binding to molecules and suppress carboxylase activity, resulting in impaired protein, fat, and carbohydrate metabolism.

They can also affect the production of genes that are important for normal development [77, 78].

Biotin covalently binds to histones using the enzyme HLCS and is involved in gene silencing, DNA repair, chromatin structure, and transposon repression [79].

Side Effects & Precautions

Contact your doctor or pharmacist if you notice any side effects after supplementing with biotin.

Source: https://selfhacked.com/blog/biotin/

Can Biotin Really Stimulate Hair Growth?

8 Biotin (Vitamin B7) Health Benefits + Side Effects, Dosage

Biotin is a B vitamin often recommended for hair health. Since biotin deficiency can lead to thinning of the hair, proponents claim that taking biotin supplements—in pill or tablet form—or using biotin-enriched shampoo and hair products can thicken hair and stimulate hair and nail growth.

Biotin is an essential vitamin—meaning that your body needs this micronutrient to function properly. The biotin you consume in foods helps your body to turn the food you eat (protein, carbohydrates, and fat) into energy.

 JR Bee / Verywell 

Taking a biotin supplement is ly effective for treating biotin deficiency. But many health products boost other health claims related to biotin supplement consumption and many of these health benefits have not been supported by scientific evidence.

So does taking a biotin supplement make your hair grow faster or fuller? There isn't enough evidence to rate biotin's effectiveness in the treatment of hair loss, according to the National Institutes of Health (NIH).

However, hair loss is a symptom of biotin deficiency, so biotin supplementation is thought to benefit people with hair loss or thinning hair who have a biotin deficiency.

Manufacturers claim that shampoo, conditioner, and hair oils, masks, or creams containing biotin can thicken hair, increase fullness, and add shine. Despite these claims, there are no scientific studies to show that biotin shampoo or any other hair product can make your hair grow faster or thicker.

Other possible benefits of biotin include the treatment of brittle finger or toenails, diabetes, diabetic nerve pain, muscular sclerosis, and diabetic nerve pain. There is insufficient scientific evidence to know for sure if biotin can treat any of these conditions.

Biotin supplements can cause problems if you ingest too much. Side effects can include skin rashes, digestive upset, problems with insulin release, and kidney problems.

According to a report published in the New England Journal of Medicine, biotin treatment was said to interfere with laboratory tests and mimic Graves' disease. As with any supplement, the safety of long-term or high-dose use isn't known. 

The U.S. Food and Drug Administration (FDA) has not established a recommended dietary allowance (RDA) for biotin. According to the Food and Nutrition Board of the Institute of Medicine, 30 mcg is the daily adequate intake for adults 19 years of age and older, which can usually be achieved through dietary consumption.

Although there is no recommended dietary allowance for biotin, proponents often recommend taking 2 to 5 mg (2000 to 5000 mcg) of biotin in supplement form daily in order to strengthen hair shafts and achieve results. Although biotin is a water-soluble vitamin (the excess is excreted in urine and feces), there is no evidence to support this recommendation and the safety of regular use of this amount isn't known.

As with other supplements, biotin hasn't been tested for safety in pregnant women, nursing mothers, children, and those with medical conditions or who are taking medications. You can find out more about how to use supplements safely here.

Biotin deficiency can occur in people who drink alcohol excessively or consume a great deal of raw egg white (which contains avidin, a protein that blocks the absorption of biotin). Two or more uncooked egg whites daily for several months has been known to result in biotin deficiency.

Genetic disorders of biotin deficiency (such as biotinidase deficiency), renal dialysis, and smoking may also increase your need for biotin. Certain drugs may reduce biotin levels, such as carbamazepine and other anticonvulsants, antibiotics, or isotretinoin.

Since biotin is produced in the intestines, people with inflammatory bowel disease or other conditions that can disrupt the balance of bacteria in the intestines may not be able to adequately produce biotin.

If you notice any symptoms of deficiency, consult your health care provider. Symptoms include thinning of the hair, brittle nails, dry skin, a red scaly rash (especially around the eyes, nose, and mouth), conjunctivitis, depression, exhaustion, hallucinations, and numbness and tingling of the arms and legs.

It is ly that you get enough biotin naturally in the food you consume. Biotin deficiency is believed to be uncommon. Bacteria in the intestines usually provides more than the body's daily requirements and biotin is also in a variety of common foods. 

Most people can meet their daily biotin needs by consuming biotin-rich foods brewer's yeast, nutritional yeast, liver, cauliflower, salmon, bananas, carrots, cooked egg yolks, sardines, nuts, legumes, and mushrooms.

Food sources of biotin (in micrograms per 100 grams) include:

  • Egg yolk (53)
  • Oats (27.0)
  • Wheat germ (17.0)
  • White mushrooms (16)
  • Spinach (6.9)
  • Cheese, brie (6.2)
  • Milk (3.5)
  • Pork (5.0)
  • Carrot (5.0)
  • Apple (4.5)
  • Tomato (4.0)
  • Beef (3.0)
  • Chicken (2.0)
  • Lettuce (1.9)

Thinning hair and hair loss can be very distressing. If you've noticed that you're losing your hair or that your hair is thinning, it's important to see your health care provider to determine the cause. (also called pattern hair loss), and hormone imbalances (such as thyroid troubles).

Although you may be eager to halt the hair loss, taking biotin tablets or supplements without being assessed poses the risk that diagnosis and treatment of the underlying cause will be delayed. 

Although biotin deficiency is considered rare, it can result in hair loss that can be addressed with supplementation. If you have symptoms of biotin deficiency or are thinking of taking it, be sure to talk with your healthcare provider to assess your levels and discuss what's best for you.

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  4. Zempleni J, Hassan YI, Wijeratne SS. Biotin and biotinidase deficiency. Expert Rev Endocrinol Metab. 2008;3(6):715-724. doi:10.1586/17446651.3.6.715

  5. Phillips TG, Slomiany WP, Allison R. Hair Loss: Common Causes and Treatment. Am Fam Physician. 2017;96(6):371-378.

Additional Reading

  • Daniells S, Hardy G. Hair loss in long-term or home parenteral nutrition: are micronutrient deficiencies to blame? Curr Opin Clin Nutr Metab Care. 2010 Nov;13(6):690-7.
  • Kummer S, Hermsen D, Distelmaier F. Biotin Treatment Mimicking Graves' Disease. N Engl J Med. 2016 Aug 18;375(7):704-6. 
  • Rajput RJ. Controversy: is there a role for adjuvants in the management of male pattern hair loss? J Cutan Aesthet Surg. 2010 May;3(2):82-6.
  • Trüeb RM. Serum Biotin Levels in Women Complaining of Hair Loss. Int J Trichology. 2016 Apr-Jun;8(2):73-7. 

Source: https://www.verywellhealth.com/biotin-for-hair-growth-89236

Biotin (Appearex) – Side Effects, Dosage, Interactions – Drugs

8 Biotin (Vitamin B7) Health Benefits + Side Effects, Dosage

Biotin is a form of vitamin B, present in many foods and available as a supplement.

Biotin is sold under many names, including Appearex, vitamin B7, vitamin H, biotina, biotine, and coenzyme R.

Many multivitamins and B-vitamin supplements also contain biotin.

Biotin works by breaking down food into sugar that your body can use for energy.

Biotin is important for healthy skin and nails, and it also keeps your eyes, liver, and nervous system working properly.

During pregnancy, biotin is important for normal fetal development.

Biotin is not stored in the body. Because of this, you can become low on biotin if you don't get enough in your diet.

Although biotin deficiency is rare, it can develop during pregnancy or in people who have poor nutrition or experience rapid weight loss.

Symptoms of biotin deficiency include hair loss, dry skin, a scaly rash around the eyes or mouth, dry eyes, fatigue, and depression.

Many people take biotin supplements in hopes of treating hair loss, cradle cap in infants, and brittle nails.

Some people also take biotin supplements to treat diabetes and nerve pain associated with diabetes, although there is not much evidence to support this type of use.

Some research also suggests that a deficiency in nutrients that include biotin could contribute to the development of type 2 diabetes.

Two 2012 studies found that biotin improved the blood sugar and insulin levels of people with type 2 diabetes when they took it along with chromium supplements.

The researchers concluded that taking biotin supplements may be beneficial for both people with diabetes and those who are obese.

Biotin for Hair

Biotin is a popular supplement for hair, skin, and fingernails, though there is little evidence to suggest that taking biotin supplements can stop hair loss or stimulate hair or nail growth.

Similarly, using biotin shampoo or other hair products is unly to produce any benefit.

There is some evidence that taking biotin supplements with other medications may help control hair loss that's associated with childhood alopecia.

Biotin Warnings

Always check with your doctor before taking any supplement. Some conditions and medications can cause low levels of biotin.

Tell your doctor if you are:

  • On dialysis
  • Smoke cigarettes
  • Eat two or more raw egg whites daily
  • Take medications for seizures
  • Have been on a long-term course of antibiotics

Biotin is a safe vitamin that is unly to cause side effects.

Nonetheless, before taking biotin supplements, tell your doctor if you are pregnant, may become pregnant, or are breastfeeding.

Do not give biotin to a child without talking to your doctor first.

Also, ask your doctor if biotin might interact with any other medications you take.

Source: https://www.everydayhealth.com/drugs/biotin