"Milk cysts" are commonly confused for acne. Milia, are small, non-inflamed cysts that develop on the skin. The tiny bumps look like whiteheads and develop when skin cells called keratin gets trapped beneath the skin's surface, they should not to be confused with acne pustules, milia are neither red nor inflamed. They almost look like a grain of sand or a hardened milky capsule and are generally small, around 1 to 2 millimeters in diameter, although some can grow larger.
Milia won't pop even if you try, and, more annoying, take a long time to resolve, they can occur anywhere on the body however they are most common around the eyes and on the cheeks, nose, and forehead. Milia aren't painful, and they don't itch.
Milia tend to hang around a lot longer than your average pimple. While most acne breakouts will naturally heal within a few day's time, milia can easily last for weeks or months.
Milia develops when a plug of skin cells, called keratin, becomes trapped just beneath the surface of the skin. Milia happen when the skin doesn't exfoliate, or shed dead cells, properly. Milia can also be triggered by an injury to the skin, such as burns, sunburns, and blistering rashes. Certain medications are also known to cause milia, especially topical corticosteroids.