ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel
  • »
  • Health»
  • Men's Health & Wellness

Hair growth cycle and causes of hair loss

Updated on December 25, 2013

Hair loss is a common problem in both men and women:

The hair loss is a very common problem in both men and women. Now, up to one third of the whole population is suffering from the hair loss problem. The most common causes associated with hair loss problem are androgen imbalance, nutritional deficiency, illness, medications, thyroid imbalance, stress, dandruff, pollution, excessive oiliness of the scalp and your genetics. Besides, frequent hair coloring/dyeing, bleaching, straightening, perming and heating also cause hair loss.However, It is important to know how hair grows and why hair loss happens. This article will cover all the answers according to the information given by the doctors.

Hair growth cycle:

The human hair follows a growth cycle with three different and concurrent phases called anagen, catagen and telogen. Characteristics of each phase to determine the length of the hair. All the phases happen simultaneously which means one strand of hair may be in the anagen phase while another is in the telogen phase. Each strand of hair has its own development cycle , once it is complete, it restarts and the new strand of hair begins to appear. The growth rate of the hair is about 1.25 cm or 0.5 inches per month and 15 cm or 6 inches per year.

Anagen phase:

Anagen phase is known as growth phase. This phase begins in the papilla and can last for two to six years.The span of this growth phase is determined by your genetics. The more a hair stays in the anagen phase the more faster and longer its growth will be. Besides, About 85% of hairs of one’s head remain in the anagen phase at any given time

Hair growth cycle


Catagen phase:

Our body decides when the anagen phase ends and the catagen phase begins. The catagen phase, also known as a transitional phase, allows follicles to renew itself. This phase lasts for two to three weeks. In this phase hair follicle shrinks due to disintegration and remains 1/6 of its original length. Consequently, lower part is destroyed, at the same time papilla breaks away and bulb is detached from its nourishing blood supply. Moreover, the hair shaft is pushed upwards and follicle simply dissipates.

Telogen phase:

Telogen phase is also known as ‘resting phase’. In this phase hair and follicle remain dormant for one to four months. It is considered that about 10 to 15% of a person’s hair remain in the telogen phase at any given time. Once the telogen phase is complete anagen phase begins and preceding hairs are pushed up and out by new hairs. This phase causes normal hair loss, for this reason, Doctors suggest that the loss of 50 to 100 hairs in a day is normal.

The hair growth cycle

Do you think hair loss problem is a beauty destroyer?

See results

Causes of hair loss:

Hair loss can happen due to different reasons and the main factor behind the hair loss problem is ‘Hormone’. However, the common reasons of the hair loss problem are given below:


Hair loss can happen due to an imbalance in androgen levels (male hormones naturally produced by both men and women) and it is medically known as “Androgenic alopecia”. DHT (dihydrotestosterone) hormone is the main factor of “Androgenic alopecia”and this type of alopecia leads to male pattern baldness and in some cases female pattern baldness. Besides, during pregnancy or after birth a woman may experience hair loss as a result of an imbalance in hormone levels. But it is temporary.

Dihydrotestosterone( DHT) affects on hair follicle



Many people are suffering from thyroid disease, a disease caused by an imbalance in thyroid hormone, and most of them are women. Thyroid hormone is responsible for basal metabolic rate, at which your body uses oxygen and energy to function of the hair growth, skin and nails. When your body produces little thyroid hormone, you are said to have hypothyroidism and your hair may become more brittle and break easily. As a result you experience hair loss. While hyperthyroidism (too much thyroid hormone production) is less common for hair loss than hypothyroidism.

Alopecia areata:

Alopecia areata is an autoimmune disease in which hair follicles are attacked by the immune system. Usually our body’s immune system acts as a natural defense system, which prevents the infection caused by bacteria or virus. But in alopecia areata our immune system becomes more active and mistakenly attacks the hair follicles, which causes hair loss.


Some diseases such as typhoid, thyroid disease, diabetes, lupus and iron deficiency anemia can cause hair loss, but when the condition is treated hair will return.


The drugs are used to treat some diseases can cause hair loss. For example, chemotherapy drugs used in cancer treatment, beta –adrenergic blockers used to control blood pressure, anti-depressant drugs and birth control pills can cause temporary hair loss.

Example of drugs that cause hair loss


Iron deficiency anemia:

Women who don’t eat iron rich foods and have heavy periods may be prone to iron deficiency anemia. In this condition blood doesn’t have enough red blood cells, which responsible for transporting the oxygen throughout the body and providing energy that you need. Iron deficiency anemia can cause extreme fatigue, weakness, pale skin, difficulty concentrating and hair loss. So, eat iron rich foods such as liver, beef, pork, fish, fortified cereals, green leafy vegetables, beans etc. along with Vitamin C rich food as it increases the iron absorption.

Scalp infections and other skin disorders:

Some scalp infections such as “Ringworm” can attack your skin of the scalp and hair follicles, which leads to hair loss. Besides, few diseases like lichen planus and some types of lupus can cause scarring and result permanent hair loss where scar appears.


Too much stress can lead to hair loss and it is known as “Telogen effluvium”. In this condition, severe stress pushes the angel hair ( growing hair) into telogen hair ( resting hair) and the affected hairs may fall out when hair washing or combing is done. So, try to make occasional trips to refresh yourself and keep your mind stress free.


Genes from both male and female parents may influence male or female pattern baldness.

Less nutrition:

When the body does not get enough vitamins and nutrients, it creates an effect on the hair. If you are on a diet please make sure you are getting enough protein and vitamins. You also need omega-3 fatty acids and other minerals. The intake of protein, vitamins and minerals can reduce the hair loss.

Cosmetic procedures and hairstyle:

Too often shampooing, bleaching, perming and dying/coloring can cause hair thinning and making the hair weak and brittle. Besides, tight braiding using hot curls or rollers and running hair picks through the tight curls can damage hair. These practices actually affect the root of the hair, so give focus on your hairstyle and cosmetic procedures.

DR. Alex Khadabi talking about DHT hormone which is the main cause of hair loss

In conclusion:

It is natural that you may lose some hair everyday because each of our hair follows a growth cycle and when the cycle ends new hair begins to appear and preceding hair falls away. Besides, most of the hair fall problems are temporary and usually remedy itself. However, if you feel that you are experiencing abnormal hair loss problem, you must consult with your Doctor or Dermatologist.


    0 of 8192 characters used
    Post Comment

    No comments yet.