Anyone, man, woman or child, can experience the onset of excessive hair loss. What may start as a few extra hairs left in the brush can escalate to handfuls of hair being left on the pillow overnight. While a certain amount of hair shedding is normal the sudden onset of accelerated hair loss can be extremely distressing.
Male and Female Pattern Baldness
The leading cause of hair loss in men is male pattern baldness (MPB) which is hereditary. The gene for MPB interacts with a hormone called DHT which is normally associated with desirable masculine traits like muscle growth and deep voice and causes it to over-stimulate hair follicles. The follicles eventually lose their ability to maintain hair growth and the end result is the loss of hair from the crown and a receding hair line.
Female pattern baldness is also affected by hormones and genes. It is characterised by a thinning of the hair all over the scalp but unlike MPB the hairline and crown are not main areas of loss and unlike men, women very rarely experience total baldness through female pattern baldness.
It is well known that chemotherapy patients often lose their hair but other forms of stress can cause the same kind of diffuse shedding including pregnancy, surgery, poor diet or some over the counter and prescription medications.
Human head hair is usually in a predominantly growing phase called anagen, with only 10-15% of hairs being in resting phase or telogen. Telogen effluvium occurs when something triggers a greater percentage of head hair to go into telogen at the same time.
Telogen effluvium can be short term, long term or chronic depending on the cause.
Tight pony tails, corn rows and excessive hairstyling can cause permanent damage to the hair follicles and root. Although permanent damage is possible, refraining from constantly pulling hair back into tight styles and stressing the root will permit hair growth to return in most cases.
Auto-immune and Inflammatory Diseases
There are several auto-immune diseases which directly or indirectly cause hair loss. One is Discoid Lupus Erythematosus, a chronic skin condition which affects the neck, face and scalp. Lupus lesions on the scalp infect and damage hair follicles and can cause permanent hair loss.
Lichen planopilaris (also known as follicular Lichen Planus) is a skin disease which can also affect the scalp resulting in redness, itching and inflammation and scarring of deep tissues resulting in permanent hair loss.
Alopecia Areata (AA) is an autoimmune disease which can affect the hair follicles all over the body. On the scalp it causes patchy hair loss. People of all ages can develop AA although it has a greater occurrence in the 15 to 30 age group.
Fungal and Bacterial Infection
There are a few fungal infections which target the scalp. One is ringworm, which is an infectious fungal infection, similar to athlete’s foot. It can appear anywhere on the body but if present on the scalp will cause patchy hair loss.
Piedra is another fungus which can weaken the hair shaft and cause patchy hair loss and
Folliculitis is an inflammation of the follicles which can, when severe, cause permanent damage to the follicle. It can be caused by a bacterial or fungal infection and results in patchy hair loss.