Milia are small harmless white skin bumps that most often occur across the nose, cheeks and chin, but can appear anywhere on the body. Infants are most prone to milia, but children and adults can also be affected, with older women having a higher occurrence of milia than other adults.
Milia resemble tiny whiteheads, but unlike whiteheads, they usually aren't surrounded by red or inflamed tissue. Milia are usually painless, but can become irritated by rough clothing.
Milia occur when dead skin cells become trapped under an outer layer of skin and then form small cysts, walled off from the surrounding tissue, according to the University of Maryland Medical Center. Milia most often occur when the skin isn't able to effectively exfoliate, or slough off, dead cells. Heavy moisturizers, creams, cleansers, suntan lotions and hair-care products can trap dead skin cells, causing milia.
Heavy sun exposure can cause thicker skin, which is more prone to milia.
Porphyria cutanea tarda, a dermatological condition characterized by skin blistering and excessive hair growth on the face and hands, can also cause milia.
Infant milia does not require treatment and will usually disappear within weeks after birth, according to MayoClinic.com.
Adult milia can be quickly removed in a dermatologist's office. The physician will first clean your skin with an alcohol swab or other antiseptic and then pierce the skin covering the milium with a sterile needle. At that point he will use a comedone extractor to apply pressure to the surrounding tissue, causing the cyst to pop to the surface of your skin.
There is no way to prevent infant milia.
Reducing sun exposure may limit future milia. Switching to noncomedogenic or oil-free skin products, using retinol creams, using home exfoliating products and regularly visiting your dermatologist for microdermabrasions or glycolic acid peels may help you prevent milia, but if you are highly prone to the condition, these techniques are likely only to reduce the number of milia you form, not prevent them entirely.
Because of the risk of infection from non-sterile tools, adults should not try to self-remove milia at home, especially in sensitive areas like the eyelids.