What is Biotin?
Biotin, also known as vitamin B7, is part of the vitamin B-complex that is considered crucial in maintaining overall health.
How Biotin Works
Biotin is a vitamin involved in the metabolism of carbohydrates, fats, and amino acids, the building blocks of protein. Like all B vitamins, it helps the body convert the carbohydrates from food into glucose (blood sugar), which is used to produce energy to fuel the body. In addition, biotin helps regulate DNA and the production of cellular structures inside the human body. Many people also consider biotin the “beauty” vitamin, because it helps promote healthy-looking hair, nails, and skin. (1) Because it is water-soluble, excess amounts of biotin are excreted in urine.
The vitamin B-complex includes essential water-soluble vitamins such as thiamine (vitamin B1), riboflavin (vitamin B2), niacin (vitamin B3), pantothenic acid (vitamin B5), pyridoxine (vitamin B6), biotin (vitamin B7), folic acid, and the cobalamins (vitamin B12). Biotin and vitamins B1, B2, and B3 are involved in different aspects of energy production and other bodily functions. Vitamin B6 assists with amino acid metabolism, and vitamin B12 and folic acid support cell division. Research suggests that vitamin B-complex multi vitamins may support wound healing, a healthy mood, athletic performance, digestion, bone health, and healthy-looking hair, skin, and nails. (2)
Biotin is an essential coenzyme for carboxylases, which are enzymes that play an important role in metabolic pathways, including in the production of glucose and fatty acids, as well as other cellular processes. A proper amount of biotin in the human diet helps maintain normal body functions, especially in the heart muscle and brain. (3) Biotin is also linked to histones (DNA-binding proteins). When biotin is molecularly bound to protein, such as histone H4, this “biotinylation” process supports DNA repair and genome stability, minimizing cellular risk for oxidation. (4)
Little is known about the bioavailability of biotin, but it seems to vary depending on the type of food being consumed. In most food, it exists in a protein-bound form, or biocytin, which is a derivative of d-biotin. (5)
Biotin may be taken as a dietary supplement, and it is also commonly found in cosmetics and personal care products, especially to support healthy-looking hair, nails, and skin. However, it is also possible to get biotin in your daily nutrition by eating a well-balanced meal. Organ meats and brewer’s yeast are good sources of biotin but consumed infrequently. There are also common sources of biotin to easily incorporate them into the diet.
Common Sources of Biotin
- Cauliflower, Raw
- Cheese, Cheddar
- Egg, Cooked
- Fortified Cereal
- Pork, Cooked
- Salmon, Cooked
- Whole Grains (6)
Daily Recommended Intake of Biotin*
- Infants 0 – 6 months: 5 mcg (microgram)
- Infants 7 – 12 months: 6 mcg
- Children 1 – 3 years: 8 mcg
- Children 4 – 8 years: 12 mcg
- Children 9 – 13 years: 20 mcg
- Adolescents 14 – 18 years: 25 mcg
- Adults 19 years and older: 30 mcg
- Pregnant women: 30 mcg
- Breastfeeding women: 35 mcg
* According to the National Academy of Sciences (7)
According to the U.S. National Library of Medicine, biotinidase deficiency is a rare hereditary disorder in which the body is unable to absorb or recycle the vitamin biotin. (8) While biotin deficiency is rare, it contributes to over 140 different neonatal genetic defects. (9) You may be at risk for a biotin deficiency if you have poor nutrition, have a metabolic disorder, are taking antibiotics or anti-seizure medicines, undergo total intravenous (IV) tube-feeding, or are pregnant.(10)
Approximately 50% of pregnant women are marginally biotin deficient, according to the Department of Nutrition and Health Sciences, University of Nebraska-Lincoln. (11) Pregnant women can become deficient in biotin because of frequent urination, causing the loss of water-soluble nutrients from the body. Pregnancy may also cause faster biotin breakdown within the body. It’s important to note that biotin deficiency in the mother may also cause fetal biotin deficiency. Taking supplements of biotin and folic acid may help prevent the risk of birth defects during pregnancy or breastfeeding. (12)
Biotin deficiency can also be caused by long-term consumption of raw eggs (approximately 20 a day) due to a protein called avidin, which binds to biotin in the small intestine, preventing its absorption. However, cooking the egg inactivates this protein. (13)
Doses of free (unbound) biotin in supplement form have been shown to support people with biotinidase deficiency, indicating that people who have problems digesting protein-bound biotin may also have an inclination for deficiency. (14) Even though it’s rare, there is no test for biotin deficiency. That’s why it’s important to keep an eye out for possible symptoms of a biotin deficiency.
Symptoms of Vitamin B7 Deficiency
- In infants: scaly scalp, hair loss, or skin rash.
- In teens/adults: hair loss, brittle or thin nails, dry scaly skin, skin rash, cracking lips, swollen tongue, dry eyes, loss of appetite, fatigue, insomnia, or depression. (15)
Dietary supplementation of biotin may help fill any nutritional gaps in the diet.
Brief History of Biotin
In 1936, biochemist and university professor Fritz Kögl and his graduate student Benno Tönnis successfully isolated biotin (then called vitamin H) from egg yolk. In Germany, biotin was referred to as vitamin H (standing for Haar und Haut), meaning hair and skin.
In the 1930s, Dr. Paul György, a Hungarian-born American nutritionist, pediatrician, and recipient of a National Medal of Science, made significant advances in defining some of the vitamins of the B-complex. He recognized that the chemical properties of Kögl's yeast growth factor and the vitamin H in eggs were similar. It was soon discovered that Kögl’s pure biotin methyl ester protected rats against the binding effects of avidin in raw egg whites, for better absorption and utilization of vitamin H. The vitamin was renamed biotin.
A few years later, Vincent Du Vigneaud and other scientists determined the structure of biotin. By 1950, biochemist Harland Wood found the importance of biotin in enzymatic processes (the “Wood-Werkman reaction”), including the biosynthesis of aspartate and the biosynthesis of unsaturated fatty acids. (16)
Biotin is a fairly recent discovery, as its structure and function weren’t fully understood until the 1990s. Today, biotin is found in many common food sources, so deficiency is rare, but supplements can help fill nutritional gaps that may occur, especially during pregnancy.
Potential Benefits of Biotin
Helps Convert Food into Energy
Several important biotin-containing enzymes are involved in the metabolism of carbohydrates, fats, and proteins for the purpose of energy production as fuel for the body. These include gluconeogenesis, the production of fatty acids, and the breakdown of amino acids, including leucine.(17)
Helps Regulate Glucose Levels
Biotin may support healthy blood sugar levels already in the normal range by balancing glucose (blood sugars). This happens when biotin-containing enzymes participate in the process of gluconeogenesis, which occurs in the liver and kidneys. It involves the production of glucose (blood sugars) from sources other than carbohydrates, such as lactate, glycerol, and glucogenic amino acids. This process helps regulate glucose levels between meals and can be stimulated by the hormones glucagon, epinephrine, and cortisol. (18)
One small study found that daily biotin supplementation of 9 mg for one month resulted in a mean 45% decrease in fasting blood glucose concentrations. (19) Other controlled studies suggest that biotin supplementation, combined with the mineral chromium, may help maintain healthy blood sugar levels already within the normal range for some overweight or obese individuals with metabolic concerns. (20, 21, 22, 23)
Supports Nervous System Function and Eye Health
People with a severely disabling neurological condition may have damaged or destroyed myelin, which is the protective covering of nerve fibers in the brain, spinal cord, and eyes. Biotin is believed to help produce myelin. Clinical research suggests that daily doses of up to 300 mg of biotin may support the health of test subjects with such health concerns. 300 milligrams is 10,000 times the commonly recommended 30 microgram daily dosage for adults. (24) In another pilot study, preliminary results report that 90% of participants had some degree of clinical improvement in vision and spinal cord health after taking biotin supplements. Research is promising but still ongoing. (25)
Supports Healthy-Looking Hair, Nails, and Skin
Hair loss or thinning hair can have a damaging emotional effect on men and women, affecting their self-esteem and self-image and often leading to depression, according to Psychology Today. Baldness can be genetic or hereditary, but it can also be caused by stress, illness, and various environmental factors. (26) Brittle, dry, thin, splitting, or frizzy hair can also be caused by heat damage, styling products, a poor diet, or the natural aging process, such as hormonal changes for senior women.
Long-term consumption of highly processed foods, white sugar, and high-fructose corn syrup may also lead to oxidative stress, premature aging of the skin, thinning of hair, and progression of some chronic diseases. This can be attributed to advanced glycation end products (AGEs), which occur when sugar molecules attach to fats and proteins without the moderation of an enzyme, disrupting metabolic pathways. (27) Biotin may help reduce that risk by protecting against glycation.
For many people, maintaining healthy-looking hair reflects physical and emotional well-being, desirability, and social or financial status. To help protect healthy-looking hair, dietary supplements containing biotin, zinc, copper, and iron (especially for vegetarians), vitamins A, D, E, niacin, and B12 may have potential positive benefits on overall appearance. (28)
Biotin supports keratin, the fibrous protein that makes up the structure of hair, nails, and the outermost layers of the skin. (29) When it comes to healthy-looking hair, biotin provides essential nutrients to support strength, texture, fullness, thickness, shine, manageability, as well as a healthier scalp. It may also support the hair growth cycle without too much shedding or breakage and helps hair withstand the effects of coloring and heat styling.
A study on women aged 21 to 75 with temporary thinning hair found that after taking a marine protein complex supplement formulated with biotin, zinc, vitamin C, and other nutrients, control-treated subjects perceived improvements in hair volume and thickness after 90 days. In addition, brittle nails reportedly returned to normal. After 180 days, the test subjects reported more hair shine, skin moisture retention, and skin smoothness with no adverse effects. (30) Another study found that biotin supplementation was found to reverse hair loss in children, but more research is needed. (31)
Other causes of temporary hair loss are attributed to side effects of certain medical treatments, such as common drugs taken by epileptic subjects. A study on rats found significant decreases of biotin in subjects undergoing drug treatments for an epileptic condition. The treatments affected the liver, hindering biotin utilization. Subjects given biotin supplements had higher biotinidase enzyme activity in serum and liver tissue, as well as less hair loss. (32)
However, hair is not the only physical trait human beings rely on to show off their perceived beauty. Healthy-looking nails and skin also play an important role in overall self-image. Unfortunately, brittle nails affect 20% of the world's population, causing splitting or cracking. (33)
Studies on hoofed animals (dairy cattle) found that biotin supplements may help to strengthen brittle fingernails or toenails in humans too. (34) In a different small study, women with brittle nails were given 2.5 mg of oral biotin supplementation per day for up to 15 months. Nail thickness improved by 25% in all participants. (35) Another study that lasted for up to 7 months for participants found that symptoms of brittle nails improved in 67% of all test subjects taking biotin supplements. (36)
Meanwhile, biotin’s role in skin health is not clearly understood, but it may be related to its effect on fat metabolism. What is clear is that biotin deficiency may lead to scaly skin or rashes, so it’s important to get enough of this important B vitamin in your diet or through supplementation. (37)
Biotin (Vitamin B7) may interfere with lab tests. According to the U.S. Food & Drug Administration (FDA), biotin may significantly interfere with certain lab tests and cause incorrect test results which may go undetected. These are included but not limited to cardiovascular diagnostic tests and hormone tests. If you are taking biotin, be sure to ask your doctor to inform the lab conducting any tests.
How to Shop for Biotin
While biotin is available in many of the foods we eat, taking a daily biotin supplement – especially if you are at risk for a deficiency – may help fill nutritional gaps in the diet. It’s important to note that biotin, when taken with alpha-lipoic acid (ALA) or vitamin B5 (pantothenic acid) may reduce effective absorption. (38)
Biotin is available from Natural Healthy Concepts as single supplements or as part of multi vitamins in gelatin, capsules, vegetable capsules, soft-gels, tablets, lozenges, oral strips, gummies, chewables, drink mixes, smoothies, energy bars, and kids’ vitamins. In personal care and beauty products, biotin is a popular ingredient in shampoos, conditioners, hair sprays, hair gels, scalp tonics, and skin serums.
Talk to your healthcare professional to see if a biotin regimen may benefit you!