There are 300,000 hairs on the human scalp.
Hair on the scalp grows approximately a half inch each month.
The shape of the hair follicle determines whether a person has straight or curly hair.
On average, healthy hair loss per day is between 100 and 150 hairs.
Hair, which is made up of dead cells filled with keratin (a protein found in nails and outer skin), grows from small pits in the dermis (the middle layer of skin just below the surface or epidermis). The pits, which are called hair follicles, cover most of the body, with certain areas having a heavier concentration than others. For example, the scalp has many hair follicles, while the soles of the feet have none.
Hair problems may be due to cosmetic causes, such as excessive shampooing and blow-drying, or due to underlying diseases, such as thyroid problems.
There are many forms of hair problems that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview.
If you cannot find the information in which you are interested, please visit the Dermatology Online Resources page in this web site for an Internet/World Wide Web address that may contain additional information on that topic.