Biotin, how does it help hair maintenance?

What is biotin or vitamin B7?

Biotin is a water-soluble vitamin, also called vitamin B7, vitamin B8, vitamin H or coenzyme R. It acts as an essential cofactor in the production of fatty acids, in the metabolism of the amino acids we ingest, and in the production and storage of sugars (gluconeogenic pathway). In other words, it helps convert fats, carbohydrates and proteins into energy. It also plays an important role in the regulation of gene expression because it interacts in DNA-related processes.

Properties of biotin

Among the health claims recognized by the EFSA (European Food Safety Authority) it is highlighted that biotin contributes to:

• Normal energy metabolism.
• Maintenance of hair in normal conditions.
• Maintenance of mucous membranes in normal conditions.
• Normal functioning of the nervous system.
• Maintenance of the skin in normal conditions.

Recommended amount of vitamin B7

The amount of daily intake of biotin recommended by EFSA varies according to age and sex.

• For adults over 18 years of age, the recommended daily amount of biotin is 40 µg/day.
• For pregnant and lactating women aged 18 years or older, the amount would be 40 µg/day for women during pregnancy and 45 µg/day for women during lactation.
• In children under 18 years of age, the amounts also vary slightly according to age and sex. For children between 4 and 10 years of age, of both genders, the recommended daily amount of biotin is 25 µg/day.
• In children and adolescents aged 11 to 17 years, the amount is 35 µg/day.

Biotin for hair loss

Hair loss can have a major impact on a person’s quality of life. There are several types of hair loss, e.g. male pattern hair loss, female pattern hair loss, alopecia areata (disruption of the immune system in the hair follicle), anagen effluvium (massive hair loss in a short period of time) and telogen effluvium (disruption of the hair life cycle with significant hair loss over a specific period of time).

Nutritional interventions have been shown to be effective in the management of hair loss, i.e. following a healthy, balanced diet containing an adequate daily intake of vitamins and minerals, especially trace elements.

Studies have shown that biotin plays an important role in the production of proteins, including keratin, the fibrous protein that is the main structural component of hair and nails, as well as being involved in the energy metabolism of hair roots in the scalp.

Benefits of vitamin B7 for hair

As we have already mentioned, adequate levels of biotin are key to both the regenerative process of the hair follicle and the formation of the proteins that make up hair. Its benefits are evidenced in a number of studies:

• Increased volume. The use of biotin in 90 healthy women increased hair volume by 13% after 12 weeks.
• Improved hair loss. In 130 individuals with telogen effluvium, the use of biotin for 3 months improved hair loss by more than 50%.
• Promotes firm, shiny hair. In a study in which 12 women took three months, it was shown that 92% increased hair volume, 82% improved hair firmness and 7% reported more shiny hair.

How does vitamin B7 act on the skin?

It is involved in the formation of the proteins that make up the skin’s structure, especially collagen, and in the skin’s regenerative process. These actions have a positive influence on skin firmness and skin replacement. The benefits of biotin on the skin include the reduction of fine line and wrinkles, skin texture, hydration and skin tone.

Biotin during pregnancy and breastfeeding

Given the importance of vitamin B7 for energy metabolism, DNA-related processes and the functioning of the nervous system, it is particularly important for pregnant and breastfeeding women to have sufficient biotin.

During these periods, women should pay particular attention to eating a balanced diet containing foods with high concentrations of biotin, so as to avoid a biotin deficit in the body. This balanced diet can be supplemented with biotin supplements at the discretion of the physician or specialist.

Foods containing biotin

Biotin is widely distributed in natural foods, although at lower levels compared to other water-soluble vitamins in foods. Foods containing high concentrations of biotin include egg yolk, liver, kidneys, and some vegetables. Liver contains approximately 1 mg/kg of biotin, while fruits and most other meats contain approximately 0.01 mg/kg. Biotin can also be found in avocados, bananas, nuts, brewer’s yeast and cheddar cheese. 

Food supplements with vitamin B7

There are supplements containing biotin that can help supplement your diet. It is available in a variety of forms in capsules, powder, vials or syrups, in combination with vitamins, minerals and plant extracts.

Some biotin supplements have recommendations for use in pregnant women, as well as for maintaining connective tissues (such as skin and hair), energy metabolism and nervous system function.

• Biotin and collagen

They are widely used in nutricosmetics. It contributes to the normal maintenance of hair and skin, and collagen is a natural protein similar to keratin that forms part of the structure of hair and nails, providing firmness.

• Biotin and zinc

The role of these two nutrients, biotin and zinc, is of great importance for maintenance of hair. Both zinc and biotin support the metabolic activities of tissues whose cells multiply rapidly, such as hair. Biotin contributes to the normal maintenance of hair, and zinc is involved in the metabolism of proteins and fatty acids which are essential elements in the structure of tissues, including hair. For these reasons, the assimilation of these two elements through a balanced diet is crucial for hair health.

• Biotin and vitamin E

Hair loss involves inappropriate oxidative reactions that can affect hair health, including the degradation not only of collagen but also of the fatty acids that make up the hair strands.

Vitamin E is recognised for its cellular protection against oxidative damage, so combined with biotin it can positively influence hair root metabolism.

• Biotin with hyaluronic acid

Hyaluronic acid is a natural component of the skin, whose hygroscopic properties make it useful for hydration, lubrication and elasticity. Its association with vitamin B7 promotes normal skin maintenance, especially during ageing.

• Biotin with iron

Both, iron and biotin, play an important role in energy metabolism and in the functioning of the nervous system, which is why their synergistic association within the diet in certain conditions such as pregnancy, growth of children and adolescents, among others, favours general well-being.

Does taking biotin have contraindications or side effects?

Clinical data reveal that there are no contraindications to biotin. It has a good tolerability profile with no related adverse effects, even in cases where it has been taken up to 9 mg/day for 4 years, 10 mg/day for 15 days, 4 mg/day for 3 weeks or 2.5 mg/day for 6-15 months.