If it is normal for the skin of the body to peel imperceptibly, it is also true that there are conditions in which the desquamation becomes excessive, visible and no longer physiological. Especially at the scalp level. Here's why and what to do
by Valeria Ghitti
In dermatology, the term desquamation indicates the loss of the most superficial skin layer in the form of small scales or flakes of skin. As the experts of AIDECO, the Italian Association of Dermatology and Cosmetology recall, this phenomenon is part of the "epidermal cell turnover", that is, the natural turnover of keratinocytes, the most numerous cells of the epidermis: desquamation represents the final process of turnover, the one in which the keratonicites detach to make room for new cells. A physiological phenomenon, therefore, and as such almost imperceptible, even if it involves the entire skin surface.
But it may happen that the flakes of skin that detach do not go unnoticed and, especially when the phenomenon concerns the scalp, are clearly visible between the hair and on the clothes. In general, in these cases, peeling is no longer a physiological condition and can also be associated with other symptoms, such as itching or redness of the skin. The root causes may be different, but there is no lack of strategies to remedy them. Let's see them in detail.
Among the factors that can determine the appearance of a flaking of the scalp, the most frequently involved include dandruff (also called Pityriasis capitis) and seborrheic dermatitis. We will deal with them better in detail and together shortly, because, as the experts of SIDeMaST – Italian Society of Dermatology recall, in a monograph dedicated to seborrheic dermatitis, the boundaries between common dandruff and seborrheic dermatitis of the scalp are not yet well defined. In particular, if there are those who consider the first a mild form of the second, there are those who consider the two conditions distinct from each other or, even, consider dandruff a paraphysiological condition.
However, there are also other conditions that can cause peeling of the scalp. In particular, although it is less frequent, it is good to remember psoriasis. This chronic inflammatory skin disease can involve the scalp and is characterized by the appearance of roundish and reddish patches, more or less itchy, covered with silvery-white scales.
Finally, according to AIDECO experts, there are cases in which the appearance of finer scales than those associated with common dandruff can actually be simply attributable to a temporary condition of dehydration and dryness of the scalp.
Dandruff and seborrheic dermatitis: what is there to know?
As anticipated, dandruff and seborrheic dermatitis are among the most common causes of peeling of the scalp. The relationship between them is not very clear. According to some authors, in fact, the term dandruff describes a generic condition of flaking of the horny layer of the scalp, regardless of the triggering cause.
According to others, such as the authors of an article published in the scientific journal Journal of Clinical and Investigative Dermatology, however, dandruff and seborrheic dermatitis can be considered the same underlying condition, which differs in localization and severity: dandruff is limited to the scalp. , the skin is itchy and peeling but does not appear inflamed, while other skin areas (such as the face and upper chest) may be involved in seborrheic dermatitis and, in addition to flaking and itching, inflammation is present. In both cases, the scales present can go from white to yellowish and appear oily or dry.
As for the triggering causes, at least three factors seem to come into play both in dandruff and in seborrheic dermatitis (also in interaction with each other):
- a secretion of sebum in the scalp greater than normal and / or altered;
- the action of a yeast, of the genus Malassezia (formerly called Pityrosporum), normally present on the scalp where it feeds on the sebum. Starting from the sebum, it produces substances that can irritate the skin, inflame it and promote the acceleration of cell turnover and, consequently, desquamation;
- individual susceptibility.
Precisely because the main culprits of scalp flaking are dandruff and seborrheic dermatitis, generally, the first recommended approach involves the use of so-called anti-dandruff shampoos, which contain substances that act in various ways:
- antifungals, which control the proliferation of Malassezia, including: zinc pyrithione, piroctone olamine, selenium derivatives, ketoconazole;
- which remove skin scales and regulate cell turnover, including: salicylic acid, tar.
They are generally found on sale in large retailers and pharmacies. They should be used regularly, following the instructions on the packaging: many have an exposure time of a few minutes to facilitate contact of the active ingredient with the scalp. With the same active ingredients there are cosmetic balms, which assist the action of shampoos or even 2 in 1 products, that is, which combine both shampoo and conditioner.
Click here to discover the shampoo that fights dandruff, itching and dryness of the scalp
Dandruff and seborrheic dermatitis are recurring conditions, so they are not completely eliminated but, with the regular use of these products, it is possible to keep the symptoms under control. However, if, after a few weeks of use, no improvement is noticed, it is advisable to contact the dermatologist: it could, in fact, be more serious forms of seborrheic dermatitis or the presence of other diseases that cause desquamation (such as the aforementioned psoriasis) that require therefore targeted interventions, through medicated shampoos and lotions available on medical prescription (they may also contain the substances already mentioned, but at higher concentrations) and / or the use of specific drugs or treatments.