Hair Growth Cycle and Hair Loss
Human hair follicles go through several stages of the hair growth cycle. Namely, they undergo anagen phase, catagen phase and telogen phase. Anagen phase represents the growing phase, the catagen is shedding phase while telogen represents resting phase. A complete cycle may last for years. It is estimated that each hair follicle completes between 10-20 complete cycles during one's lifetime. Furthermore, approximately 1% or even fewer of scalp follicles are in the catagen phase.
It is normal for all humans to lose approximately 100 hairs per day. However, if the loss exceeds the limited number this points to the presence of an abnormal shift in normal hair growth cycle. Fortunately, hair loss associated with normal anagen-catagen-telogen cycling activity is considered normal and it is known as temporary hair loss. The lost hair will be easily replaced with new growth from follicles that enter anagen phase.
Most Common Causes of Temporary Hair Loss
Many people confuse hair breakage with hair loss. In people who have fine hair the hair is prone to breakage. The condition may even aggravate if one uses aggressive chemicals (those found in shampoos and other hair products or chemicals found in swimming pools etc). Whether the person is actually losing hair can be easily confirmed if one counts all the hairs that have fallen and if they exceed the number of 200 and all of them have visible roots we can say that a person is suffering from hair loss.
Excessive usage of many cosmetic products may be responsible for temporary hair loss. Furthermore, even insufficient hygiene of the scalp and inadequate washing of the hair may be associated with temporary hair loss. Apart from these mechanical causes of hair loss temporary hair loss is also associated with physical stress, emotional stress, child birth, intake of certain medications, hormonal disorders and inappropriate diet.
Emotional and physical stress represent a common cause of temporary hair loss. The problem is, fortunately, transient and one must learn how to deal with stress and avoid repeated hair loss. Hormonal changes such as hypothyroidism are typically accompanied by temporary hair loss. Once the level of hormones is brought to normal hair becomes strong and healthy as it used to be. Hormonal changes in pregnant women are also potential triggers for temporary hair loss. Only if the hair loss during pregnancy continues after childbirth a woman must undergo tests and examinations since this may point to persistence of hormonal imbalance. And finally, if one's diet lacks in essential nutrients, minerals and vitamins there is an increased chance for temporary hair loss. Once the diet becomes normal and rich in the previously mentioned substance the lost hair is successfully restored.