Hair loss can be due to: • Decreased growth of the hair • Increased shedding of the hair • Breakage of hairs • Conversion of thick terminal hairs to thin vellus hairs Hair cycle Hair grows in a cycle: • Anagen (living growing hair), • Catagen (in-between phase) and • Telogen (resting or falling-out phase). • Recently a new phase, ketogen, has been recognised; this is when the follicle is empty, after the telogen hair has fallen out and before the anagen hair is visible on the scalp.
The following are some of the symptoms of Hair loss: Anagen hair loss Anagen is normally for two to seven years. Hair loss occurs when anagen is interrupted by certain medications (e.g. anti-cancer drugs), or by the ‘autoimmune’ disease, alopecia areata. Anagen hair is tapered or broken-off. Telogen hair loss Telogen lasts 4-6 months and is terminated by a new anagen hair. The result is falling off of hair with a bulb at the end. It is normal to lose 50 or more telogen hairs a day, and even little more in autumn and winter. Excessive shedding results in telogen effluvium, often a couple of months after an event such as child-bearing, fever, an operation, weight loss or certain medications. Sometimes there will be no recognizable cause, and the shortened hair cycle can continue for years (chronic telogen effluvium). New growth can be seen at the hairline as a sign of recovery. Pattern hair loss (androgenetic alopecia) Genetic and hormonal influences result in gradual thinning of scalp hair with age as male or female pattern (androgenetic) hair loss. It is apparent in about 50% of individuals by the age of 50 years. Internal conditions Other causes of hair loss are associated with poor quality hair: • Iron deficiency • Deficiency of thyroid hormone Replacement of iron or thyroid hormone respectively may result in prompt regrowth. Hair shaft abnormality If hair loss first occurs in childhood, it may be due to a genetic hair shaft defect. These are diagnosed by microscopic examination of the hair, and sometimes by scanning electron microscopy. Following are the hair shaft abnormality : • Fractures of hair shaft : trichorrhexis nodosa, trichoschisis • Irregularities in the hair shaft: trichorrhexis invaginata , Marie-Unna hypotrichosis (uncombable hair), pili bifurcati, beaded hair • Coiling and twisting of hair shaft : pili torti (twisted hair), woolly hair Anagen hair loss in a child may be due to ‘loose anagen syndrome’. Scarring alopecia Trauma, infection and various skin diseases may injure the hair follicle resulting in localised areas of scarring,cicatrisation and bald patches in which there are no visible follicles; this is called ‘cicatricial alopecia’. Infections like Staphylococcal folliculitis or boils, and ringworm (tinea capitis) also can be reason for scarring alopecia. Skin diseases like, lichen planopilaris, frontal fibrosing alopecia, discoid lupus erythematosus and scleroderma. Scarring hair loss of unknown cause is known as pseudopelade. Scalp conditions tinea capitis psoriasis -thick plaques of scale Seborrhoeic dermatitis atopic dermatitis. Trauma Hair can be pulled out by tight curlers or certain hair styles, sometimes resulting in permanently thinned areas (traction alopecia). The hair shafts can be broken by heat (hair dryer), or chemicals (perming solution or bleach) or brushing too often. Trichotillomania is a form of alopecia resulting from repetitive pulling, plucking and breaking of one's own hair.
All the above causes and risk factors responsible for the hair fall should be first assessed. The treatment pattern will be decided as per the diagnosis and a tailor made diet and other accessory mode would provide a great help.
