Most of us look at the eyebrows as a patch of hair that has an aesthetic purpose and it is often shaped for cosmetic purposes. Although the exact purpose of the eyebrows is not conclusively understood, it is believed to be prevent water or sweat from falling on to the eyes itself. For most people its function is of little concern compared to its cosmetic purpose. As with hair anywhere on the body, eyebrow hair and the follicles from where it arises can be prone to the same diseases and disorders which may lead to hair loss..
However, the effects of alopecia reach far beyond symptoms of depression and include anxiety, obsessions, dissatisfaction with one’s appearance, and low self-esteem (Al-Mutairi and Eldin, 2011, Dlova et al., 2016, Hunt and McHale, 2005, Schmidt et al., 2001). There can be significant disturbance in a patient’s social life because they may change their hair style, clothing, or avoid social meetings (Al-Mutairi and Eldin, 2011). One study reported that 40% of surveyed women described marital problems and 63% had career-related issues that they ascribed to their hair loss (Hunt and McHale, 2005). These effects seem to occur regardless of patients’ age, race, or degree of hair loss (Dlova et al., 2016, Hunt and McHale, 2005, Schmidt et al., 2001). Another study of more than 200 women found that this psychologic morbidity occurs with equal frequency in women whose hair is typically covered by a headscarf (Erol et al., 2012).
Hair loss is something that everyone experiences sooner or later, but some get it earlier than others. Losing hair prematurely can be traumatic. Because of that, there is an infinite number of products that claim to cure and reverse the problem. But what if you could find out the likelihood that you will experience hair loss so that you could prevent it before the symptoms even showed? Researchers in the United Kingdom have reportedly found a way to predict who is at risk.
Eyebrows protect the eyes from sweat that trickles down the forehead. They also protect the bony ridges above the eyes. In addition to the above, the eyebrows play a very important function in facial expression and body language. Eyelashes protect the eyeball from small foreign bodies and irritants and stimulate the closing reflex. Both eyebrows and eyelashes play a very important cosmetic function, and thus contribute greatly to the self esteem of an individual.
Thyroid hormone receptors were detected in both dermal and epithelial compartments of the human pilosebaceous unit. T4 and T3 decrease the apoptosis of hair follicles and T4 prolongs the duration of anagen in vitro. Thyroidectomy delays initiation of anagen. Administration of thyroxine advances anagen, initiation of which is however delayed once toxic doses are given. Therefore, ratio of telogen to anagen hairs is increased in hypothyroidism as well as hyperthyroidism. Thus, the hair follicles are affected in thyroid disorders, and madarosis is caused due to disturbances in hair cell kinetics. Hypothyroidism is associated with generalized hair loss probably due to coarse, dull, and brittle hair with reduced diameter. The eyebrows and eyelashes may also be lost. Loss of lateral one-third of eyebrows known as Hertoghe sign is a characteristic sign of hypothyroidism. Some people also refer to it as Queen Anne's sign, after Anne of Denmark whose portrait with shortened eyebrows has been interpreted by some as indicative of the presence of goiter, even though such a fact has not been proved by any known sources of information. Madarosis may even be the presenting sign in hyperthyroidism. In hyperthyroidism, there is thinning with breaking off and shortening of hair. Madarosis can also occur in hypopituitarism, hypoparathyroidism, and hyperparathyroidism.