We all grow hair everywhere on our skin except a few places, such as our lips, palms of our hands, and palms of our feet. Much of our hair is so small and so thin that we cannot even see it. Hair is formed in follicles in our skin by the production of a protein called keratin. Hair goes through three cycles, growing, transitory, and resting. During the growing cycle, called the anagen cycle, the hair will grow at a rate of up to 6 inches per year, for a period of 3-6 years. As people age, the rate their hair grows at slows. There are on average about 100,000 to 150,000 hairs on the adult head. Under normal conditions, we lose about 100 per day, and these are replaced with new hairs. Approximately 90 percent of the hair on your head at any given time should be in the growing cycle.
There are many types of hair loss. Each type of hair loss has its own cause, and may present with different patterns. Here is a list of the different types of hair loss, each with a brief description.
Involutional alopecia is hair loss that is a natural, slow hair loss in which the hair begins to thin with age. It is caused by a higher percentage of hair entering the third cycle, the telegen phase which is also known as the resting phase. During the resting phase, which may last up to three months, the hair does not grow and will eventually be shed.
Androgenic alopecia affects men and women. It is a genetic condition that is the cause of male pattern baldness. It can affect someone into their early twenties, or even their teens. Women are typically not affected until their 40?s.
Alopecia areata affects children and young adults mostly, and it causes a patchy type of hair loss. It may cause complete baldness. Generally all the hair loss is temporary.
Alopecia universalis affects all the hair of the body, causing loss everywhere including, pubic hair, eye lashes, and eye brows.
Trichotillomania is the condition in which a person pulls their own hair out. It is a mental condition affecting mostly children.
Telegen effluvium is usually temporary. The cause is unknown, but for some reason a large number of hairs enter the third stage, the resting stage, at the same time and then fall out. The hair is later regrown.
Hair loss is not anything any of us look forward to. If you are experiencing hair loss, you should see your dermatologist to determine which type of hair loss that you have. Depending on the type, it is sometimes possible to reverse hair loss by changing medications, improving diet, using a hair growth product, or other means. The success of your treatment will depend in large part on what the underlying cause is. Be prepared though, because a lot of hair loss is permanent. Only your dermatologist can determine if your hair loss can be reversed or not.