THE HAIR GROWTH CYCLE
We're born with all our hair follicles already in place. While some may change in size over time, we don't develop any new ones after birth. As adults, we have about 100,000 individual strands of hair. It's completely normal to lose some 40 to 100 strands every day. Normal hair loss is the result of the growth cycle of the follicles, similar to an 'on off' system. This means that when an old hair 'dies', the growing phase starts again for a new hair to replace it. The hair growth cycle has three different phases:
1. Anagen
The Anagen phase is the growing phase or the 'on' phase, which lasts for an average of approximately 1,000 days in the human scalp, but can range from 2 - 6 years. During the Anagen phase, hair cells proliferate rapidly. The hair shaft grows in diameter and the hair reaches maximum length.
2. Catagen
The Catagen phase lasts only 1 - 2 weeks - it's the transitional or regressive phase before the resting phase begins. It's essentially when the hair stops growing.
3. Telogen
The Telogen phase is the final resting stage or 'off' phase, which lasts for about 5 - 6 weeks.
When the old hair is in the Telogen phase, activity in the hair follicle is renewed. A new hair in the Anagen phase develops and forces the old Telogen hair out. This is when hairs are lost and you might notice them in the bath or in your brush or comb.
As mentioned, on average 40-100 hairs are lost due to this natural growth process every day. This is normal hair loss and accounts for the hair loss seen every day in the shower and with hair combing. In healthy follicles these hairs will soon be replaced by new hair.
A variety of factors can alter the normal hair growth cycle and cause temporary or permanent hair loss including medication, radiation, chemotherapy, exposure to chemicals, hormonal and nutritional factors, thyroid disease, generalized or local skin disease, and stress.
You can read more about the causes of hair loss in our Types of Hair Loss section.
FACTS ABOUT HAIR LOSS
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The average person has 100,000 - 150,000 hairs on their head
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One hair fiber can support the weight of 100 grams
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The main component of hair is the keratin, which also holds the responsibility for the elasticity of the finger nails
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Hair is the second fastest growing tissue in the body (bone marrow is quicker). A hair grows 0.3-0.5mm per day
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In any given time, about 10% of the hairs are resting and the rest are growing
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Everyone loses more than 40% of his/her hairs - about 100 hairs a day
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Hair loss will be visible only after losing more than 50% of hair
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More than 50% of men above the age of 50 suffer from hair loss
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Between a third and two thirds of all women experience thinning hair or hair loss at some stage in their life.
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The most common form of hair loss in women is Effluviums (all over thinning of hair)
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Common reasons for hair loss include: postnatal, menopause, HRT, The Pill, stress, diet and trauma.
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Great looking hair makes you feel good - it also attracts the attention of the opposite sex.
It is part of our personality.
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Hair gives us key information about a potential mate's health. Healthy hair tends to mean a healthy person.
MYTHS RELATED TO HAIR LOSS
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Frequent shampooing contributes to hair loss.
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Hats and wigs cause hair loss.
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100 strokes of the hair brush daily will create healthier hair.
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Permanent hair loss is caused by perms, colors and other cosmetic treatments.
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Shaving one's head will cause the hair to grow back thicker.
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Standing on one's head will cause increased circulation and thereby stimulate hair growth!
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Dandruff causes permanent hair loss.
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Hair loss does not occur in the late teens or early twenties.
TYPES OF HAIR LOSS
Alopecia Areata
Alopecia Areata is thought to be an auto-immune disease of the hair, this means that the body's immune system acts as if the hair follicles are foreign and attacks them. White blood cells called T- lymphocytes attack the hair follicle which causes the hair to stop growing and enter into the telogen (resting) phase, then about 3 months later, when the resting phase is over, the hair will then fall out. Only when T-lymphocytes stop attacking the hair follicle will new hair grow.
Alopecia Areata initially appears as a rounded bare patch about an inch across. It affects both men and women equally and is often experienced first in childhood. According to a survey taken in America, one person in every hundred is likely to experience Alopecia Areata at sometime in their life. Many people affected with Alopecia Areata will only have one experience of hair loss with regrowth occurring afterwards, however it is estimated that in approximately 20 percent of cases, hair loss recurs or becomes permanent.
There are three types of Alopecia Areata, which are named according to their severity. These are as follows:
Alopecia Areata; mild patchy hair loss on the scalp Alopecia Totalis; loss of all scalp hair Alopecia Universalis; loss of scalp and all body hair
Studies have shown that Viviscal® proves effective in the treatment of all three types of Alopecia. See our clinical trials section for more information.
Self Induced Hair Loss
Some damage to the hair is self-inflicted sometimes consciously or unconsciously. The two main types of self-induced hair loss are Trichotillomania and Traction Alopecia.
Trichotillomania
Trichotillomania is self-induced hair loss, which results from the continuous pulling or plucking of the hair. It occurs most commonly among young children, adolescents and women and affects twice as many females as males. The hair is often pulled out in distinct patches on the scalp however, some individuals also pull out eyebrows and eyelashes.
The treatment for Trichotillomania often involves counseling or psychiatric help, however in some cases an antidepressant may be prescribed.
Traction Alopecia
Traction Alopecia is usually caused by continuous and excessive pulling on the hair due to various types of hairstyling. Ponytails, buns, braiding and cornrows often result in a continuous pulling on the hair. This traction gradually results in hair loss. If this type of traction and hair loss continues for an excessively long period of time then the hair loss may become permanent. Generally however a change in hairstyle that reduces the traction on the hair and hair follicle is all that is required in the treatment of Traction Alopecia.
Androgenetic Alopecia
Hair loss resulting in thinning is known as alopecia. When it is related to hormones (androgens) and genetics, it is known as androgenetic alopecia, or more commonly just balding. Male pattern alopecia is characterized by a receding hairline and/or hair loss on the top of the head. A similar type of hair loss in women, female pattern alopecia, results in thinning hair on the vertex (top) of the scalp but is generally less severe than occurs in males. The Norwood-Hamilton Scale (Fig 1.) shows the progressive stages of male pattern hair loss. Left untreated, male pattern hair loss is a condition that usually gets worse.
Fig 1. Norwood Hamilton Scale
Fig 2. The Ludwig Scale
The Ludwig Hair Loss Scale (Fig 2.) measures the typical progression of female-pattern hair loss.
Studies have shown that Viviscal® proves effective in the treatment of Androgenetic Alopecia.
Telogen Effluvium
Telogen effluvium occurs when sudden or severe stress causes an increase in the shedding of the hair. With telogen effluvium, a sudden or stressful event can cause the hair follicles to prematurely stop growing and enter into a resting phase. The hair will then stay in the resting phase for about 3 months after which time a large amount of hair will be shed. Often the person involved will have recovered from the event before the hair loss occurs. In most cases the hair loss is temporary and the hair soon recovers. However in some cases the hair loss continues until the underlying cause is fixed. Telogen effluvium appears to affect more woman than men because more of the precipitating events such as childbirth are experienced by women.
Telogen Effluvium can be caused by the following:
Hormonal changes
Infections of the scalp
Major Surgery/Chronic Illness
Severe psychological stress
Crash diets/inadequate protein
Drugs/Medication
Hormonal Changes:
There are many reasons for hormonal changes within the body; a lot of these can result in hair loss such as:
Hair Loss after Child Birth:
It is quite common for some women to experience some hair loss approximately 3 months after childbirth. This hair loss is triggered by the sudden changes in hormone levels.
Some statistics suggest that 20 percent of mothers lose hair after childbirth and others suggest a figure closer to 45 percent. Fortunately, in most cases the hair will return to normal 9-12 months after the child's birth.
Many women notice that their hair is thicker and healthier during pregnancy, this is due to the increased levels of hormones estrogen and progesterone, which cause more hairs than normal to remain in the growth phase. When the child is born however, many of the hair follicles that had delayed entering the resting phase suddenly enter the resting phase due to a rapid drop in hormone levels. As a result, these hairs are then shed about 3 months after the birth.
Hair Loss resulting from taking the Birth Control Pill:
Birth control pills affect the hormone levels within the body and these hormone levels can affect hair growth. In some cases, hair thinning may occur due to the male hormones present in some contraceptive pills. This type of hair loss is similar to pattern baldness or Androgenetic Alopecia. However, discontinuation of the pill can result in hair loss similar to that which occurs after childbirth due to the drop in hormone levels.
Hair Loss resulting from Thyroid Gland malfunction:
Generally the first test a doctor or specialist is likely to carry out on a patient who is experiencing hair loss is a thyroid function test, as a thyroid problem may result in hair loss. Two types of thyroid problems can occur and either of these problems can result in hair loss. These conditions are Hypothyroidism (the under production of Thyroxine) and Hyperthyroidism (the over production of Thyroxine).
Hair loss may occur from either hypothyroidism or hyperthyroidism. In some cases hair loss is minimal, however some individuals experience severe hair loss. Fortunately hair loss is usually reversible with proper treatment. If you suspect that you have a problem with your thyroid function then you should visit your doctor.
Infections of the scalp:
Infections such as ringworm can invade the hair and skin of your scalp, leading to hair loss. Once infections are treated, hair generally regrows.
Major Surgery/Chronic Illness:
The shock involved in a major operation can result in sudden hair loss. Also after micro graft and mini graft surgery where follicles are transplanted on the scalp telogen effluvium almost always occurs. Due to the shock of surgery the hair follicles will fall out within about 3 months after which time new hairs will grow from the transplanted follicles.
Some cancer treatments will cause hair cells to stop dividing. Hairs become thin and break off as they exit the scalp. This occurs one to three weeks after the treatment. Patients can lose up to 90 percent of their scalp hair. The hair will regrow after treatment ends.
Severe Physiological Stress:
Some people experience telogen effluvium or sudden diffuse hair loss after a traumatic event such as the death of a family member or someone close, an accident, abuse or any other severely traumatic event. These events may trigger hair follicles to enter the resting phase prematurely in which case an increase in the amount of hair shed will be noticed about 3 months after the event. When the stressful situation is over or the body adjusts to it, the hair usually grows back.
Crash Diets/Inadequate Protein:
Some people who go on crash diets that are low in protein, or have severely abnormal eating habits, may develop protein malnutrition. The body will save protein by shifting growing hairs into the resting phase. Massive hair shedding can occur two to three months later. Hair can then be pulled out by the roots fairly easily. This condition can be reversed and prevented by eating the proper amount of protein and, when dieting, maintaining adequate protein intake.
Drugs/Medication:
Some prescription drugs may cause temporary hair shedding. Examples include some of the medicines used for the following: gout, arthritis, depression, heart problems, high blood pressure, or blood thinner. High doses of vitamin A may also cause hair shedding.
The following is list of some drugs that have been reported to have a side effect of hair loss:
Alloppurinol (for the treatment of Gout)
Heparin (blood thinner)
Coumarin (blood thinner)
Clofibrate (Cholesterol lowering drug)
Gemfibrozil (Cholesterol lowering drug)
The above drugs are only a few of the drugs that have been reported as contributing towards hair loss. If you suspect that prescription drugs that you are taking are causing hair loss you should discuss this with your doctor.
