What are milia?
Milia are small, white or whitish cysts on the skin. They are most common in infants and most commonly appear on the face, although they occur in other age groups and on other parts of the body. About 40-50 percent of newborns in the U.S. have milia.
“Milia” is the plural word; one is called a “milium.” A milium is also known as a milk spot or an oil seed.
They do not require treatment. In babies, milia usually do not last longer than a few weeks. People old enough to care about how they look might seek to have them removed.
What are the different kinds of milia, and what causes them?
- Milia occur when dead skin cells get trapped under the skin and form cysts.
- Neonatal milia are found in about half of all infants. They often appear on or around the nose. They are sometimes confused with “baby acne,” which is not the same thing. Unlike baby acne, milia can be present at birth.
- Primary milia, which often appear on the eyelids, forehead, cheeks or genitals, can occur in children or adults. Primary milia are not associated with damage to the skin. Like neonatal milia, they usually clear up on their own, but it might take a few months.
- Secondary milia happen after the skin is damaged in some way – burns, rashes, blisters, excessive exposure to sunlight. The milia develop as the skin heals. Another name for secondary milia is traumatic milia. They can also be caused by a reaction to a heavy skin cream or ointment.
- Juvenile milia are commonly linked to an inherited disorder. The milia are sometimes present at birth, and sometimes show up later.
- Milia en plaque is an unusual condition that mostly, but not exclusively, affects middle-aged women. The milia are clumped together on a raised patch of skin, usually behind the ears, on an eyelid, or on the cheek or jaw.
- Multiple eruptive milia, another rare form, are groups of milia that appear over weeks or months, usually on the face, upper arms or upper abdomen. They are sometimes itchy.