Diffuse alopecia is a form of alopecia and refers to a reduction in the density of the hair. It is found with greater frequency in the female population compared to the male population. Diffuse alopecia is the result of a negative influence on the basic development of the hair life cycle. Essentially, immature hairs fall off and thinning occurs diffusely in the parietal region. Diffuse alopecia usually subsides after a period of months and thinning is restored.
The life cycle of the hair
The life cycle of the hair is constantly repeating and each hair has its own cycle which lasts for a different length of time. As far as head hair is concerned, we lose about 100 hairs every day. The hair life cycle is divided into 3 main stages:
- Anagen: It is the first stage, during which the hair is born and grows and takes its complete form. The anagen stage has the longest duration.
- Catagen: It is the stage in which various physiological processes take place in order to cause the existing hair to fall and the new hair to take its place, starting a new life cycle. The catagen stage lasts 2-3 weeks.
- Telogen: It is the stage in which the fall of the existing hair occurs and the new one starts to be born, developing its bulb.
Classification of Diffuse Alopecia
Diffuse alopecia depending on its temporal duration is classified into 3 types, which are:
- Acute diffuse alopecia: Hair is lost suddenly.
- Subacute diffuse alopecia: The fall of head hair occurs gradually and lasts for several months.
- Chronic diffuse alopecia: The hair fall recurs and lasts for more than 6 months.
Causes of diffuse alopecia
The most likely causes for the occurrence of diffuse alopecia are:
- Intense stress
- Inherited factors
- Psychological trauma
- Chronic diseases
- Strict diets
- Autoimmune diseases
For the female population in particular, the periods of menopause, pregnancy and childbirth are periods when the intense hormonal changes cause generalised thinning of the scalp.