You only have to see how self conscious people are about scaly dandruff on their collar to know that this is true. 
 

At present these pages are simply an outline of the normal hair growth cycle and some causes of hair loss. 
 
We will expand upon this, but the links we give below are probably more informative that we shall ever be!  I shall try to reduce the techno-jargon to a level that even I can understand. 
 

 
There are many conditions that can cause premature hair loss.  
 
Alopecia Areata is a condition that can cause widening patches of baldness although this may be temporary.  Alopecia Areata can be caused by illness, pregnancy, trauma, thyroid problems, diabetes, anemia, crash dieting, steroids and chemotherapy.   
 
Male pattern baldness (alopecia) may be genetic but is usually accelerated by stress, junk food and a highly paced lifestyle. 
 
It would be foolish and misleading to claim that any herbal hair tonic will be an effective hair loss treatment in every case.  A topically applied hair loss product cannot be a total treatment for thinning hair due to some of the causes listed above.   
 
If you have an underlying medical condition you should seek qualified advice and treatment for that.  However, positive, natural hair-care will help hair to regrow and return to normal more quickly. 
 

The Hair Growth Cycle  

An understanding of hair loss requires a basic knowledge of the growth cycle observed in hair growth. Three phases are described. 
 
1. Anagen, or the growth phase in which actual growth of the hair is seen.  This is measured in years and varies from person to person 
 
2. Catagen, or the resting phase in which growth of hair ceases for a few weeks.  
 
3. Telogen is the  phase where hair will be shed natuarally. 
 
All of these phases are normal and that even in a healthy head of hair an average of fifty to one hundred hairs a day are lost. Under normal circumstances, the hair that is shed is replaced by a new hair from the same follicle.  
 
However, when too many of the hairs stop being replaced naturally (i.e., the balance between anagen and telogen is lost and the scales tipped in favor of telogen), visible hair loss begins.  
 
Usually half a person's hair density must be lost before the loss is very evident. As a person agesr, the hair shafts also become thinner and this give the appearance of actual hair loss - visible thinning.  

 
There are numerous factors that can cause hair loss. By far, the most common is androgenic alopecia better known as male pattern baldness which appears to be largely due largely due to hormonal influence.  
 
However, other causes of hair loss can exist and it is important to recognize this in the rare patient who presents with hair loss not due to androgenic alopecia.  
 
The reason for this is two-fold: First and most obvious,  if there is an underlying cause for the problem, that cause must be identified to allow proper treatment for the hair loss. Also, in the event a disease is identified, it is important to treat the disease as it most likely affects more that just the hair.  
 
An example of a disease associated with hair loss is hypothyroidism (abnormally low level of thyroid gland activity). This is seen more in women and in a clinical situation,  women complaining of hair loss are more suspect of having this as an underlying cause for their hair loss.  
 
As mentioned, the most common type of hair loss seen is androgenic alopecia or male pattern baldness.  In the past, many thought the reason for this type of hair loss was an excess of testosterone in the affected individual. Currently, most experts in this field attribute the cause to be dihydrotestosterone (DHT).  DHT is a naturally occurring substance that results from metabolism, or breakdown, of testosterone 
 

The most informative links  

My recommendation would be that you visit these in order.  The Oxford Hair Foundation is excellent despite funding links with Procter & Gamble.  Keratinmay annoy you with the advertising, but is a mine of information. 
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