Can we prevent the occurrence of milia?

The milium cysts are skin growths filled with trapped keratin beneath the skin. The causes of their appearance have not been fully clarified yet. However, studies suggest several triggering factors.

Firstly, milia can form spontaneously, without any external action. When dead skin cells do not exfoliate, they inhibit the growth of hair follicles. Above them, new skin forms and traps them beneath the surface, resulting in the formation of microcysts.

They can also appear following a trauma caused by skin irritation, such as after the use of harsh cosmetic products. They are also believed to have a genetic origin with hereditary transmission. Lastly, the exposure to UV rays which can damage skin cells and the integrity of the skin, the application of topical corticosteroids which can weaken the epidermis, and an association with dermatological diseases are among other potential causes.

Most of the time, the occurrence of milia is spontaneous, without a specific cause. This is particularly the case in newborns affected. However, although the presumed origins of milia have not all been proven, advice on actions to adopt can be found on the Internet, which could prove beneficial in limiting the appearance of these milia.

The recommendations that could potentially reduce the risk of observing milia on the skin, which are most commonly found, are:

• Avoid the use of greasy creams.

  The application of this type of cream on the face could potentially block the pores attached to the hair follicles, thereby forming milia.

• Limit your exposure to UV rays and protect yourself from the sun.

  sunscreen with a minimum SPF 30.

It is important to note that these recommendations have not been scientifically proven. They are merelyhypotheses. Nevertheless, they are still beneficial for overall quality of life and are applicable in many situations.

However, one particular piece of advice stems from a behaviour observed in a study as promoting milia. This is theuse of mechanical tools in cosmetics, such as skin brushes for example. Indeed, some follicles could close due to the abrasive action of the accessory, or pieces of epithelium could become embedded in the skin during treatment and thus block the hair follicles, subsequently leading to milia. We therefore advise you to avoid their use.

In truth, to this day we have no way of predicting the onset of milia. It is merely a type of benign self-defence behaviour against aggressions.

• MONASH S. Formation of milia following abrasive treatment for postacne scarring. Archives of Dermatology (1953).

• TSUJI T. Milia induced by corticosteroids. Archives of Dermatology (1986).

• BERK D. R. & al. Milia: A review and classification. Journal of the American Academy of Dermatology (2008).

• BARBAROT S. & al. Les grains de milium de l’enfant. Annales de dermatologie et de vénéréologie (2009).

• GALLARDO AVILA P. & al. Milia. StatPearls (2023).