Is Vitamin B7 the Ultimate Secret to Healthy Hair or Just a Myth?

Biotin is a water-soluble vitamin that is part of the B complex. It plays a crucial role in the metabolism of carbohydrates, fats, and proteins, facilitating the conversion of food into energy. In addition, it is essential for the health of skin, nails, and hair, as it participates in the synthesis of keratin, the main protein of these structures.

As it has been widely promoted as a miracle supplement to improve hair health in hair products, it is essential to critically analyze its effectiveness and consider the potential disadvantages associated with its use. While biotin is vital for various bodily functions, its indiscriminate supplementation may not be necessary for everyone. Most people get enough biotin through a balanced diet, and excess supplementation could be unnecessary and potentially problematic.

Biotin deficiency, for example, is relatively rare in individuals with a balanced diet. However, certain factors may increase the risk of deficiency, such as prolonged consumption of raw egg whites, which contain avidin, a protein that inhibits biotin absorption. Symptoms of a deficiency include thinning hair, rashes around the eyes, nose, and mouth, and brittle nails. Diagnosing a biotin deficiency can be tricky due to the lack of specific tests and the similarity of its symptoms to other conditions. Therefore, it is crucial to consult a health care professional before starting any supplementation.

Do biotin supplements promote hair growth in people without deficiency?

Although biotin is essential for hair health, scientific evidence supporting its supplementation in individuals without deficiency is limited. Most studies showing significant benefits focus on people with preexisting deficiencies. Therefore, in individuals with adequate biotin levels, additional supplementation may not offer noticeable improvements in hair health.

As we already said in our article, Biotin: the darling of hair products, unnecessary use of biotin supplements can lead to excessive intake, which could interfere with certain laboratory tests, such as thyroid function tests, causing inaccurate results. In addition, some reports suggest that high doses of biotin can cause side effects such as acne or digestive problems.

Note: To maintain optimal levels of biotin, it is advisable to consume foods rich in this vitamin. Among the most notable sources are egg yolks, nuts, seeds, fish, and certain vegetables such as spinach. Although these foods are beneficial, it is important to note that cooking can reduce the biotin content in some of them. Therefore, proper preparation is essential to maximize the intake of this vitamin.

What do experts think about using biotin for hair health?

Dermatology experts point out that while biotin is crucial for hair health, supplementation in non-deficient individuals may not produce the desired effects. They recommend focusing on a balanced diet and addressing other factors that can influence hair health, such as stress management and avoiding harsh hair treatments.

Relying solely on biotin supplements without addressing other aspects of hair care can lead to unrealistic expectations and unsatisfactory results. In addition to hair loss, a biotin deficiency can manifest itself with symptoms such as skin rashes around the eyes, nose, and mouth, brittle nails, fatigue, depression, hallucinations, and numbness or tingling in the extremities. It is important to note that these symptoms are nonspecific and can be confused with other conditions, making an accurate diagnosis difficult without proper evaluation by a health care professional.

The belief that biotin improves hair growth in people without deficiency has been widely promoted in the commercial arena, but scientific evidence to support this claim is scarce. Most studies linking biotin to improved hair or nails have been conducted in people with underlying conditions affecting keratin production, such as brittle nail syndrome or specific nutritional deficiencies.

What do clinical studies say about biotin and hair growth?

In terms of clinical evidence in humans, the most cited studies in favor of biotin are mostly case series or observational studies without a control group. For example, a review published in the Journal of the American Academy of Dermatology evaluated 18 cases in which biotin supplementation showed improvements in hair and nail quality.

However, all of the patients in these studies had underlying pathologies that warranted supplementation, such as nutritional deficiencies, metabolic diseases, or medical treatments that affected keratin synthesis. Healthy individuals were not included, limiting the generalizability of the results. Furthermore, a review article in Skin Appendage Disorders concluded that there are no randomized clinical trials showing that biotin improves hair growth in people without deficiency. Most claims about its effectiveness come from anecdotal testimony or from studies of low methodological quality. Some in vitro (laboratory) studies have shown that biotin is involved in keratin synthesis and hair follicle health. However, these studies cannot be directly extrapolated to humans, as the experimental conditions do not reflect the complex metabolism of a living organism. In animal models, biotin deficiency has shown negative effects on coat quality, supporting its importance in hair health. However, in these studies, animals were subject to extreme biotin deprivation, a condition uncommon in humans on a balanced diet.

Since scientific evidence does not support the use of biotin in individuals without a deficiency, dermatology experts often recommend a more comprehensive approach to hair care. This includes:

Balanced nutrition: Hair depends on a variety of nutrients, such as iron, zinc, vitamin D, and protein. A diet poor in these elements can affect hair health much more than a lack of biotin.

Stress reduction: Chronic stress can trigger hair loss through telogen effluvium, a condition in which follicles enter the resting phase prematurely.

Avoid harsh treatments: Excessive use of heat, harsh chemicals, and hair styles that apply tension can damage the hair fiber and contribute to its weakening. Is it safe to take biotin supplements without medical necessity? Although biotin is a water-soluble vitamin and excess is excreted in urine, high-dose supplementation can cause problems. For example:

Interference with medical tests: High doses of biotin have been documented to alter the results of thyroid and cardiac function tests, which can lead to misdiagnoses.

Possible side effects: Some people have reported acne breakouts, digestive discomfort, and allergic reactions after taking high-dose biotin supplements.

Are biotin supplements combined with other ingredients more effective?

There are numerous hair growth supplements on the market that combine biotin with other ingredients such as collagen, zinc, vitamin D, folic acid, and plant extracts. The idea behind these products is that the synergy of various nutrients could improve hair health more than biotin alone. However, scientific evidence on the effectiveness of these combinations remains limited.

For example, some studies have suggested that zinc and vitamin D play a key role in hair follicle health. A review in the Dermatology and Therapy Journal found that zinc deficiency is associated with hair loss, and supplementation in people with low levels could be beneficial. (PubMed) The same is true for vitamin D, deficiency of which has been linked to alopecia areata and other types of hair loss. However, in individuals with normal levels of these nutrients, there is no clear evidence that supplementation provides any additional benefit.

On the other hand, collagen is a popular ingredient in these supplements, but its relationship to hair growth is more speculative. Although collagen is an important structural component in the skin and scalp, there are no solid clinical studies confirming that its oral intake translates into better hair growth.

While these products may be appealing, there are several factors to consider:

Lack of strict regulation: Many supplements are not subject to the same regulations as drugs, meaning the quality and concentration of ingredients can vary between brands.

Unnecessary or excessive doses: Some formulas contain amounts far exceeding the recommended daily intake of certain nutrients, which does not necessarily improve effectiveness and, in some cases, could lead to adverse effects.

Unrealistic expectations: Advertising for these products often suggests that anyone will see an improvement in their hair, when in reality they may only be helpful in cases of nutritional deficiency.

Bottom Line

Despite biotin's popularity as a hair health supplement, scientific evidence supporting its effectiveness in people without a deficiency is limited. Most of the available studies have been conducted in individuals with underlying medical conditions that affect keratin production, and there are no controlled clinical trials demonstrating significant benefits in healthy people. While biotin is an essential nutrient for hair growth, over-supplementation does not guarantee visible improvements and can lead to unrealistic expectations. Additionally, relying solely on biotin to treat hair problems can lead to overlooking other important factors, such as overall nutrition, stress management, and reducing harsh hair treatments.

Supplements combined with biotin and other ingredients such as zinc, collagen, or vitamin D may be helpful in cases of deficiency, but their effectiveness in people without deficiencies remains uncertain. Additionally, the lack of strict regulation in the supplement industry and the potential for side effects make it important to consult with a health care professional before taking these products. Ultimately, the best strategy for hair health is not based on a single vitamin, but on a comprehensive approach that includes a balanced diet, a healthy lifestyle and proper hair care.

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Vitamin B7: is it the ultimate secret to healthy hair or just a myth?