Study: Biotin Deficiency In Women With Hair Loss

Many hair growth supplements contain biotin, but science is skeptical about its effectiveness.

Biotin – also known as vitamin H or vitamin B7 – is a popular ingredient in many hair growth supplements. It’s an important factor in many biological processes, including the growth of healthy skin, nails, and hair. Symptoms of biotin deficiency include hair loss, face rashes, red eyes, and even psychological symptoms such as depression. Hair loss usually only occurs when there is a more severe deficiency. In people with a biotin deficiency, taking a biotin supplement can help, but can biotin improve hair growth in otherwise healthy people?

A study by Dr Ralph Trüeb, MD, published in 2016 in the International Journal of Trichology, looked at how often biotin deficiency was seen in women with hair loss. What he found casts doubts on the indiscriminate use of biotin supplementation.

A total of 503 women and girls between the ages of 9 and 92 who contacted the Center for Dermatology and Hair Diseases Professor Trüeb, with complaints of hair loss – and whose biotin levels were measured – were included in the study. Those of the patients who were taking a biotin supplement during the time were excluded.
The 503 women were divided into three groups:

• Those who were biotin deficient
• Those who had suboptimal biotin levels
• Those with optimal biotin levels

The result showed that 38% of the hair loss patients were considered biotin deficient and ended up in the first group. Only 13 % of these women suffering from hair loss had optimal levels of biotin (group 3). The rest, 49%, had suboptimal levels.

In other words, almost 4 out of 10 women in this study had a biotin deficiency. The results indicate that it is more common to find a biotin deficiency in women experiencing hair loss, than to find that they have optimal levels of the vitamin.

The result also shows that it is possible to experience hair loss even with perfect biotin levels, meaning that biotin levels alone are insufficient to explain hair loss across the group. Therefore, taking a biotin supplement will not fix the hair loss problem for everyone. Essentially, Trüeb’s study shows that hair loss in women is due to multiple factors, with biotin deficiency being only one of many possible causes.

Furthermore, the study looked at the results of trichograms (a hair analysis method that involves plucking about 100 hairs from different parts of the scalp and examining them under a microscope) – a procedure that roughly half of the women in group 1 and group 3 had performed. The trichograms detected diffuse telogen effluvium (a particular form of hair thinning where the hair strands goes into the resting phase prematurely) in 24% of the women in both groups. Since the percentage of women with diffuse telogen effluvium was the same between the groups, it shows that trichograms are not very helpful in detecting hair loss relating to biotin deficiency since they are neither sensitive nor specific.

More interestingly was the result when looking closer at the women where diffuse telogen effluvium was detected. In the biotin deficient group, 35% had associated seborrheic-like dermatitis – a common skin disease that can look like eczema and can result in dandruff among other symptoms. In the group of women with optimal biotin levels, not a single one had the dermatitis condition. This may indicate a connection between the presence of dandruff and a biotin deficiency, and taking a patients biotin levels is advisable when dandruff or, more specifically, seborrheic dermatitis is found.

This study indicates that biotin deficiency is a potential cause of hair loss in women, but that it is not the only cause of hair loss. In cases of known deficiency, biotin supplementation has shown to be effective, but in women with optimal biotin levels, taking additional biotin would not improve hair growth.

The quantity and quality of a person’s hair is very much influenced by their diet. Calories, protein, and vitamins and minerals play a vital role in growing healthy hair, and there are several nutritional deficiencies that can affect hair growth. This study showed a relationship between low biotin levels and hair loss, but it does not support using biotin as a hair growth supplement for cases where biotin levels are normal. It is worth noting that biotin deficiency is quite uncommon as intestinal bacteria produce more than the body’s requirements. Instead of indiscriminate biotin usage, this study recommends testing patients with hair loss for biotin levels, both to avoid an unhelpful remedy and to encourage discovery of the specific reason for hair loss.