The causes

of hair loss

To lose 50 to 100 hair per day is normal and this is the renewal process of hair. However, some people may suffer from excessive hair loss at a certain period of their life.

The most common cause of hair loss is attributed to a hereditary factor.

There are several other reasons for explaining hair loss among which a reaction to hormonal, chemical or nutritional factors, a medical treatment, chemotherapy, thyroid disease, local or generalized skin disease, stress, etc. Some of these causes have a temporary effect (up to 3 or 4 months), while others are permanent.

Hair structure

three layered strand

A strand of hair is the visible part above the skin and the deeper segment under the scalp is known as the root. Composed of three layers, each strand has a diameter of 70-100 microns.

THE CUTICULE is the external layer of a strand of hair, which is formed of hardened protective cells. It is without pigment and arranged much like the shingles on a roof, intertwined and overlapping. These thick cells collectively give hair its texture.

THE CORTEX is under the scalp and directly related to the hair volume. The fibrous cells of the cortex contain keratin (the principle ingredient in hair), and melanin (the pigment that gives hair its color).

THE MEDULLA is the innermost center, composing 0 to 10% of the volume. In the case of very fine hair, the medulla is absent.

THE ROOT is the living part of the hair anchored in the scalp. At the tip of the root, a slightly larger area known as the bulb bears a thick, whitish appearance when one plucks a strand of hair.

THE PAPILLA is the curved and empty area at the base of the bulb. It connects the hair to the head. Here, the blood vessels and nerves meet and the hair receives its nourishment.

The hair cycle

a cyclical growth

Depending on various factors, the quantity of hair varies from one person to another. It is estimated that a person would have between 100,000 to 150,000 hairs on the scalp. A hair cycle begins every 2 to 6 years and lasts 3 years in average.

The cycle is genetically programmed and it follows 3 stages.

During the anagen phase, also known as the growth phase, the hair grows about 1cm per month. The anagene phase lasts between 2 to 5 years.

The hair bulb finds itself within the skin, and it will remain there until the resting phase.

The catagen phase is a transitional phase that lasts about 3 weeks. This phase marks the end of the active formation of the hair and the bulb.

The telogen phase, also known as the resting phase, occurs when the bulb reaches maturity. The keratin filled bulb emerges from the papilla and surrounds itself with a chain of cells, called the epithelium-lined sack.

Female alopecia

hair loss in three stages

About one-third of women experience hair loss at some point in their lives. After menopause, two-thirds of women experience a form of hair loss or thinning.

The most common type of hair loss in both sexes is androgenetic alopecia, or male/female pattern hair loss. In women, androgenetic alopecia begins with gradual thinning at the part line, followed by increasing diffuse hair loss radiating from the top of the head.

Male alopecia

hair loss in five stages

Most men will experience a form of hair loss or thinning at some point in their lives. Usually hair loss is gradual, but in some instances it may be sudden due to a medical problem or an underlying condition.

The most common type of hair loss in both sexes is androgenetic alopecia, or male/female pattern hair loss. In men, hair loss usually begins above the temples, and the receding hairline eventually forms a characteristic M shape; hair at the top of the head also thins, often progressing to baldness.