An Overview of Milia

Milia are small cysts that form on the skin. They are also known as "milk cysts." Milia form when a protein called keratin gets trapped under the skin. The tiny bumps look like whiteheads, but they are not acne. Unlike acne, they don't develop in a pore and are not red or inflamed.

This article discusses the causes and diagnosis of milia. It also covers treatment and offers tips for prevention.

Symptoms of Milia

Milia are hard, raised cysts that form under the outer layer of skin. They are white to yellowish in color. They can look like a grain of sand or a hard, milky capsule.

Milia are usually small, around 1 to 2 millimeters in diameter. Some can grow larger. Milia won't pop and can take a long time to go away.

Milia can show up anywhere, but they are most common on the face. They may appear around the eyes and cheeks, nose, and forehead. Milia don't hurt or itch. They are annoying but harmless.

Milia usually last longer than pimples. Pimples heal within a few days, but milia can last for weeks or months.

An aggressive form of milia exists, but it is rare. It is called "multiple eruptive milia." Eruptive milia form on the head, neck, and trunk. They may last for weeks or months. Unlike other kinds of milia, eruptive milia are usually inflamed.

What Causes Milia?

Milia form when keratin becomes trapped just under the skin. Keratin is the protein that gives skin its structure. It can become trapped when the skin doesn't exfoliate, or shed dead cells.

Milia are often confused with acne, but they are not the same. Acne comedones, or blemishes, form when pores are blocked. Milia don't form within pores. They form just under the top layer of skin.

Milia are very common. They can happen at any age. Even babies can have milia. In fact, up to 50% of healthy newborns develop milia. In newborns, milia usually go away within a few weeks.

Most cases of milia have no clear cause. Some people, though, are more prone to getting them. If you have acne and blackheads, you probably also have milia. But milia can form even if your skin is clear.

Milia can also form after skin injuries like:

• Burns
• Sunburns
• Blistering rashes

Some medications can cause milia, especially:

• Topical corticosteroids
• The chemotherapy drug 5-fluorouracil

Certain procedures like Fraxel laser treatments can also cause milia.

When milia happen on their own, they are called "primary milia." Milia that form after disease or injury are called "secondary milia."

How Milia are Diagnosed

Healthcare providers can often diagnose milia based on how they look. But there are other causes of small, white skin bumps. If the cause isn't clear, a dermatologist can remove a cyst and look at it under a microscope. This can help with diagnosis.

Basal cell carcinoma, a type of skin cancer, can also look like a pearly white bump. If you have a bump that does not go away and you aren't sure what it is, call your healthcare provider.

Is There a Treatment for Milia?

Milia usually go away on their own. Sometimes it can take months or years. If you don't want to wait, talk to your healthcare provider. Medications like retinoids and glycolic acid can help your skin shed and replace cells faster.

You can also have the bumps extracted. The process is simple and you will see results right away.

Don't try to extract milia yourself at home. To remove milia, a healthcare provider makes tiny incisions on your skin. The healthcare provider removes the plugs with tweezers and a magnifying glass. Dried cells might be removed beforehand. This is done with a topical exfoliant.

Your healthcare provider or dermatologist can help you decide on the best way to treat your milia.

Can Milia Be Prevented?

There is nothing you can do to completely prevent milia. You can decrease your chance of getting them, though. If you are prone to milia, it might be because of what you put on your skin. Thick, heavy moisturizers and eye creams can trigger milia. 

It might be a good idea to change your skincare routine. Look for products labeled "oil-free" or "non-comedogenic." These products are less likely to clog your pores. They are also less likely to trigger keratin overgrowth.

Summary

Milia can be annoying, but they are harmless. You can decrease your chances of getting milia by changing your skin routine. You can also have them removed. Talk to your healthcare provide about the different treatment options for milia.