Hair Loss (Balding) and Thinning Hair – Causes in Men and Women

Hair loss (balding) and thinning hair is a common problem that affects both men and women although it is more frequently seen in adult males. With a host of hair growing and thickening products on the market, it is important to understand how hair loss occurs in order to make the best choice. In many cases, hair loss cannot be treated or treatment is not very effective and other options like a hair transplant may have to be considered.

Normal Hair Growth

The hair growth cycle comprises of three phases:

  1. Anagen Phase
    Also called the growth phase. Almost 80% of hairs are in this phase at any time. The total time period of the growth phase is from two to seven years. The average growth of hairs during this phase is about 10 to 12cm per year.
  2. Catagen Phase
    Also called the catagen phase. This is a transitional stage in which the hair cells (hair follicles) decrease in size and the lower part is destroyed. The duration of catagen phase may lasts up to a few weeks.
  3. Telogen Phase
    The third phase  brings the hairs to a resting position. This phase lasts for 5  to 7 weeks. About 10 to 15% of hairs are in the telogen phase at any one time. The hair cells enter the growth cycle again upon completion of the telogen phase.

The human head loses some 100 to 125 strands of hair per day. New hair grows at the site where old hair is lost. The hairs remain in continuous replacement phase; when a hair falls down; a new hair comes out from its place. However, the problem starts when the number of falling hairs rises considerably and are not replaced by new hairs at a sufficient rate if at all.

Types and Patterns of Hair Loss (Baldness)

A person’s medical history is important in order to understand and identify the type of baldness. This will assist with deciding upon the correct treatment. Some of the pattens of baldness includes :

Alopecia areata

This is a spotty baldness and occurs in patches. It is usually temporary and can occur on other areas of the body like the beard.

Male Pattern Baldness

This is the most common pattern of hair loss in men which constitutes around 95% of cases. A receding hair line and balding at the top of the hair is usually seen. The hair loss may be partial or sometimes complete. It is caused by genetic predisposition and hormonal changes.

Female Pattern Baldness

Complete baldness in women rarely occurs. Usually hair thins or is lost from the side, front or crown but the hairline remains although it recedes slightly. It is often due to  hormonal disturbances and genetic causes. This pattern of baldness can be observed at any age, however; it is more common near cessation of menses (menopause) and sometimes after pregnancy. Women with certain gynaecological conditions like polycystic ovary syndrome (PCOS) may also notice hair loss even at a young age.

Scarring Alopecia

Scarring occurs due to prolonged or severe inflammation of the scalp as a result of injuries like burns or skin conditions like psoriasis. Another common cause is the use of strong chemicals like hair straighteners (relaxers), dyes and bleaching agents or perming substances.

Telogen Effluvium

Loss of hair due to severe illnesses or certain conditions like stress. It is a reversible condition once the person returns to good health or the stress is removed. Hair loss is most evident when waking up in the morning and seeing strands of hair covering the pillow or while washing and combing where the hair falls off in handfuls.

Other causes of temporary hair loss may be due to certain hairstyles, like braids or tight pigtails, which is known as traction alopecia or after the use of certain drugs as is seen with chemotherapy in cancer patients and this is known as anagen effluvium.

Common Causes of Baldness in Men

In men the most common cause of hair loss is the familial tendency (heredity). It has been ascertained that the derivative of male hormone (testosterone), which is called as DHT (dihydro-testosterone), inhibits the growth of scalp hairs.

The effect of DHT is variable. It shortens the anagen phase of hair cycle and the overall size of the hair follicles are decreased. The hairs become shorter, thinner and may not regrow after being shed. Baldness due to DHT is also known as androgen alopecia or male pattern baldness. It may also be seen in women due to hormonal disturbances which results in increased DHT.

Common Causes of Baldness in Women

Hormonal imbalances are among the more common causes of hair loss in women. Several conditions in which the normal hormone levels are disrupted will result in thinning hair and hair loss. The reverse may also occur – a pregnant woman may experience good hair growth and hair thickening during pregnancy due to high levels of the female hormones, oestrogen and progesterone, during this time. However after delivery, a woman may develop significant hair loss due to normalization of hormonal levels. Hair loss also occurs in menopause as the oestrogen and progesterone levels drop.

Other Causes of Baldness (Both Men and Women)

There are several causes of hair loss that may affect both and women.

  • Systemic illnesses like Addison’s disease,  hypertension (high blood pressure), syphilis, HIV, Cushing’s syndrome, thyroid disorders, skin diseases like seborrheic dermatitis and psoriasis.
  • Organic and inorganic chemicals, especially which are present in shampoo,  hair creams, gel, hair softeners, chemical straighteners/relaxers.
  • Dandruff and fungal infection of scalp (tinea capitis).
  • Stress – physical, mental and emotional.
  • Continuous or repeated pulling of hairs (trichotillomania)
  • Vitamin and mineral deficiencies like the deficiency of zinc or iron
  • Poor diet – apart from vitamin and mineral deficiencies, poor nutrition (starvation, eating disorders, severe dieting) will affect normal body processes.
  • Drugs – cholesterol and lipid lowering drugs, blood thinners, gout medication and cancer drugs.