Hair Loss

Alopecia or hair loss is the medical description of the loss of hair from the head or body, sometimes to the extent of baldness. Unlike the common aesthetic depilation of body hair, alopecia tends to be involuntary and unwelcome, e.g., androgenic alopecia. However, it may also be caused by a psychological compulsion to pull out one's own hair (trichotillomania) or the unforeseen consequences of voluntary hairstyling routines (mechanical "traction alopecia" from excessively tight ponytails or braids, or burns to the scalp from caustic hair relaxer solutions or hot hair irons).

In some cases, alopecia is an indication of an underlying medical concern, such as iron deficiency.

When hair loss occurs in only one section, it is known as alopecia areata. Alopecia universalis is when complete hair loss on the body occurs, similar to how hair loss associated with chemotherapy sometimes affects the entire body.

Causes

• Androgenic alopecia (Male pattern baldness)
• Fungal infection such as "black dot" tinea or tinea capitis
• Chemical breakage such as over processing, or frequent use of chemical relaxer
• Heat damage as from repeated hot comb use
• Chronic exposure to traction on hair shaft such as Traction alopecia
• Compulsive hair pulling such as trichotillomania
• Hyperthyroidism or Hypothyroidism
• Iron deficiency
• Telogen effluvium resulting from physical or psychological stress
• Hereditary disorder of the hair shaft or genodermatoses
• Secondary syphilis can cause "moth eaten hairloss"
• Discoid lupus erythematosus or chronic cutanous lupus erythematosus
• Lichenplanopilaris
• Pseudopelade of Brocq
• Tufted folliculitis
• Dissecting cellulitis
• Alopecia mucinosa
• Keratosis follicularis spinulosa decalvans
• Adverse effect from certain drugs such as chemotherapy
• Radiation therapy
• Testosterone booster tablets.

Latest research

In May 2009, researchers in Japan identified a gene, SOX21, that appears to be responsible for hair loss in humans.