Hair loss

Hair loss, commonly known as alopecia, is a common problem that can be distressing. This is due to the problem usually result in major impact on patient’s quality of life. Therefore, in order to develop an effective treatment for hair loss, it is important to understand various forms of alopecia and the basic yet fundamental science behind it. The ongoing research on alopecia provides important information about abundant stem cell populations, impaired hair cycle and hair follicles and pathophysiology of alopecia. As a result we will better understand the basic science behind this condition [1, 2].

Androgenetic alopecia hair loss

  • A common form of hair loss in both men and women.
  • 50% of men are affected by age 50, and 40% of women by age 70
  • In men, this condition is also known as male-pattern baldness. So, hair thinning begins above both temples, while over time the hairline recedes to form a characteristic “M” shape
  • In women this is at the crown with preservation of the frontal hairline
  • Cause: This type of alopecia is caused by the effect of dihydrotestosterone on hair follicles. As a result hair follicles become miniaturised.

Alopecia areata

  • Equally affects both sexes, with usual onset before age 30
  • Most common areas which this issue occurs are scalp and beard regions
  • Round areas of complete baldness with retained follicular ostia
  • Cause: Autoimmune destruction of hair follicles involving cell-based and hormonal immunity

Telogen effluvium

  • a form of temporary loss that usually happens after stress, shock, or a traumatic event.
  • The hair thinning for less than 6 months however in chronic versions it’ll last more than 6 months
  • It usually occurs on the top of the scalp.

Anagen effluvium

  • A form of hair falling out associated with chemotherapy and radiation.
  • In this disorder the hair shaft is narrowed and fractured

Traction alopecia

  • Results from tension applied to hair for a prolonged period of time. For example from hairstyles such as ponytails and braids, as well as hair styling devices
  • Especially common among African-American females due to their association with certain hairstyles
  • Typically, this type of hair thinning is temporary


  1. Qi, J. and L.A. Garza, An overview of alopecias. Cold Spring Harb Perspect Med, 2014. 4(3)
  2. Phillips, T.G., W.P. Slomiany, and R. Allison, Hair Loss: Common Causes and Treatment. Am Fam Physician, 2017. 96(6): p. 371-378.