In terms of hair loss, hair is produced in hair follicles, which are located in the outer layer of the skin. These follicles produce new hair cells (called keratinocytes because they produce keratin, the main component of hair) continuously, pushing the old cells out of the skin and forming a string of dead cells: hair.
Is it normal to lose hair?
The average adult has over 100,000 hairs on his or her head and loses up to 100 of them every day because of normal hair shedding. Normally, this hair loss is not noticeable because lost hair is quickly replaced by new hair, but as people age the rate of hair growth slows down and more hair follicles go into the resting phase, so there is less hair growth. And the hair that does grow becomes thinner and shorter. This is called involutional alopecia and is normal during aging.
Other types of hair loss that can affect men and women include:
- androgenic alopecia, a genetic condition characterized by a receding hairline and gradual loss of hair from the crown and frontal scalp
- alopecia areata, which causes patchy hair loss in children and young adults
- alopecia universalis, when all of the body hair falls outs, including eyebrows and eyelashes
- scarring alopecias, caused by skin inflammation and other skin disorders which cause scars that stop hair from regenerating
Several factors can influence hair loss, such as abnormal levels of the hormone androgen, genetic predisposition, drugs (including chemotherapy and blood thinners), autoimmune disease-causing skin inflammation, some medical conditions (including thyroid disease, lupus, anemia, eating disorders, and diabetes), illness, burns, and even childbirth. Also, lifestyle can worsen hair loss, for example shampooing too often or harsh hair treatments such as perms and bleaching, or some diets, such as low-protein or severely calorie-restricted diets.
Is there a solution against hair loss?
Although there are many remedies in the market that claim to restore hair, there is still no real solution to hair loss. Some drugs, such as Rogaine and Propecia, can provide a modest regrowth of hair and can slow hair loss, but they cannot completely stop hair loss or restore a full head of hair. Other treatments include corticosteroids to fight inflammation due to immune disorders, and hair transplantation, where plugs of skin from parts of the scalp that still have active hair follicles are relocated into the balder areas of the scalp. Although this procedure may be effective in generating some new hair, it is a long and costly procedure.
But the ultimate solution against baldness may be just around the corner. Recent research shows that stem cells, particularly umbilical cord blood stem cells, can enhance hair growth. Last year, researchers from the Nanjing Medical University in China showed that umbilical cord blood stem cells can successfully be differentiated into hair follicle cells, using the supernatant of hair follicle cells to reprogram the stem cells.
A 2018 study from the Chung-Ang University in Korea found that human umbilical cord blood mesenchymal stem cells can advance the onset of hair’s active growth phase (called anagen) and hair follicle neogeneration, partly thanks to the growth factors produced by these cells, including Insulin-like growth factor binding protein-1 (IGFBP-1) and vascular endothelial growth factor (VEGF). These studies show that umbilical cord blood stem cells may be the key in the fight against hair loss, bringing some hope for the millions of men and women who dream of recovering a full head of hair.
Bu, Z., Wu, L., Yu, X., Zhong, J., Yang, P., & Chen, J. (2017). Isolation and characterization of in vitro culture of hair follicle cells differentiated from umbilical cord blood mesenchymal stem cells. Experimental and Therapeutic Medicine, 14, 303-307. https://doi.org/10.3892/etm.2017.4456
Dong, Ho Bak, Mi, Ji Choi, Soon, Re Kim, Byung, Chul Lee, Jae, Min Kim. 2018. Human umbilical cord blood mesenchymal stem cells engineered to overexpress growth factors accelerate outcomes in hair growth. Korean J Physiol Pharmacol. Sep; 22(5): 555-566