Every normal human hair can be classified in cycles – it grows (anagen), rests (catagen), and then falls out (telogen). Nomally,this cycle recurs approximately every one year. Growth phase for about 3 years, with a range between 1.5-2 and 5-6 years.The percent of the scalp hair is in a resting phase that last between one and four month . After 1 to 4 months, the resting hair falls out and new hair starts to grow .The average scalp contains about 100,000 hairs. Each individual hair survives for an average 5 years and the average rate of growth of human hair has been stated to be approximately 0.9mm/30days and on the crown of the scalp it averaged approximately 1.5mm/30days, being slightly less on the margins. Scalp hair grows faster in women than in men but the average rate over the whole body is greater in men than in women.As a proved theory shaving has no effect on the rate of growth in spite of various hormone factors like estrogen and thyroxine have been shown to influence the rate of hair growth. During pregnancy, there is an increase in growth phase and following childbirth, large number of hair enter resting phase, leading to increased hair loss from about 3 months post partum . This process may also be caused by a number of medications and illnesses.
Genetic baldness is caused by a hair follicle’s failure to make new hairs and not by massive hair loss.The other causes of hair loss such as 3 to 6 month after major surgery,fungal infection, sever illness, sex-related hormonal imbalance particularly in women, abnormal thyroid function, systemic disease like diabetes, chronic renal failure, lupus, iron deficiency and some medicines such as Vitamin A derivatives, anti high blood pressure(anti hypertension) and heart disease and antidepressants as well. Shedding 50 to 100 hairs a day is a normal occurrence and is replaced by a new hair. Based on the latest findings and our experience in clinic around 40 to 60 percent of the normal population experience normal hair loss by the time they rich 40-60.
The vast majority of women with hair loss have no endocrine abnormality, in some women the hair loss may be accelerated by high androgen(male prominent hormones) levels. At least 90% of adult men experience some degree of hair loss on scalp after puberty. The age of onset of male hair loss mostly is 20-30 years and just a small number of them achieve total baldness. There is no any doubt that familial tendency to baldness plays the main role and involves both sexes. Luckily there are now a number of effective treatments to arrest the progression of hair loss and stimulate regrowth in a considerable proportion of individuals although vulnerable people may be kept away from commercial centres where profit is the only motivation.
Depending on your hair loss type, treatments are different. Stopping a medicine if that’s the cause of your hair loss, correcting a hormone imbalance, some simple diet, medications like Minoxidil solution,topical and oral Finasteride, hair transplantation and so on can be recommended by your doctor. According to the American Hair Loss Association 99% of all products being marketed in the less than ethical hair loss treatment industry are completely ineffective for the majority of those who use them. Always keep in mind that early treatment and early intervention by your doctor has a critical role in prevention of excessive hair loss because when hair follicle damaged it’s never reversible and on that particular area you experience long life baldness .
Excessive bleaching, permanent waving(a perm) and straightening procedures may cause excessive weathering and fragility of hair.
As a rule all shampoos are a suitable detergent for washing hair based on your hair type that leaves the hair in good condition but not a treatment for hair loss ! Also the majority of topical products which claim they prevent of hair loss truly their effect has not been approved and they’re not effective that’s why I recommend whenever you hear about a new treatment, you’d better carefully study the component, and the feedback confirming them and last but not least always consult a dermatologist for any treatment and while you experience an unusual pattern , bold spots on your eyebrows or beard, history of present or previous mense irregularity,any sign of redness and scaling in a particular area,rapid onset of losing hair and any sign of systemic problem like fatigue,low grade fever,intolerance to cold temperatures or fatigue and prompt process of hair thinning.
Hossein Yavari, MD
American Board of Hair Restoration Surgery
Fellowship in Cutaneous and Mohs Surgery, University of Miami, USA