In general, 90% of the hair on your head grows approximately one half inch per month and continues for two to six years.

When the growth phase ends, usually the hair shaft begins a 'rest' period and then sheds. Only 10% of your hair is resting at any one time.

On the average, 50 to 150 hairs are lost each day but most hair regrows because the follicle remains. Considering the typical adult head has about 100,000 shafts of hair, that is not a lot of loss!

Eventually a new hair shaft begins to grow from the root embedded inside the hair follicle, pushing out the old shaft as it grows. When shedding significantly exceeds growth, baldness occurs.

Normally, hair loss is caused by heredity, hormones and age. Genes target hair follicles that are sensitive to the hormone dihydrotestostesrone, causing them to shrink, This 'shrinkage' results in overall thinning over the entire crown of the head. In rare cases, there are other reasons for hair loss. Autoimmune disease, the use of certain drugs, illness and stress may cause hair loss or promote early male pattern baldness. Severe trauma to the head accompanied by scarring can cause permanent damage to hair follicles. Even tight hair styles like braids can create tension and cause the hair follicles to become inflamed. The hair follicles are destroyed and hair growth is terminated.

Additional Informational Sites:

Male Hair Loss & Pattern Baldness in Men