What Causes Milia and How to Get Rid of Them

Milia, also known as “milk cysts,” are tiny white bumps that form on the skin. Even though they look like whiteheads, they are not acne. They’re actually small cysts caused by a protein called keratin that gets trapped under the skin. 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.

What Are Milia?

Milia are hard, raised cysts that form under the outer layer of skin. Milia form when keratin and dead skin cells become trapped under the skin. This debris hardens over time and clumps together to form small, hard cysts.

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.

Types of Milia

Milia are categorized as either primary or secondary. Secondary milia occur after an injury, burn, or other condition clogs the ducts under the skin. Primary milia develop on their own, without a secondary cause.

Milia affects both children and adults. Some of the types of milia include:

• Neonatal milia: Milia on newborn skin is referred to as neonatal milia. Neonatal milia is common around the nose but can also appear on other parts of the face, scalp, or torso. Milia affects up to 50% of newborn babies and usually disappears on its own during the first few weeks of life.
• Juvenile milia: This type of milia is usually caused by a rare genetic disorder that causes abnormal cell growth such as Bazex-Dupré-Christol syndrome or pachyonychia congenita. 
• Milia en plaque: This type of milia is associated with autoimmune skin disorders such as lichen planus or discoid lupus. Milia en plaque are much larger than typical milia and usually appear on the face.
  
• Multiple eruptive milia: This is a rare, aggressive form of 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.
• Traumatic milia: This is a secondary type of milia caused by skin injury such as burns or exposure to irritating chemicals like poison ivy.

Symptoms of Milia

Milia are very small bumps on the skin that 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.

What Causes Milia?

Keratin is the protein that gives skin its structure. It can become trapped when the skin doesn't exfoliate, or shed dead cells. When this happens, milia can form.

Most cases of milia also have no clear cause, but some do. In both children and adults, milia can occur after injury to the skin or because of a condition that causes blistering. In rare cases, milia can be caused by a genetic condition. In older adults, milia may occur as the skin loses its ability to shed skin cells. 

Neonatal milia has no clear cause.

Some people are more prone to getting milia. 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
• 5-fluorouracil (a chemotherapy drug)

Certain procedures like Fraxel laser treatments can also cause 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. However, sometimes it can take months or years. You can choose to treat them conservatively at home or see your healthcare provider to have them removed.

At-Home Care

Don't try to squeeze milia or remove them yourself at home. The most important thing you can do is keep your face clean by washing twice a day with a gentle soap. Look for mild products labeled "paraben-free." Pat your skin dry to prevent chafing. 

Neonatal milia do not need to be treated. Keep your baby's skin clean and talk to your pediatrician if the bumps are still present after 6 months of age.

Medical Treatments

If you don't want to wait for milia to clear up on its own, talk to your healthcare provider. Treatments are available that can remove milia and prevent them from returning:

• Medications: Retinoids and glycolic acid can help your skin shed and replace cells faster.
  
• Extraction: A healthcare provider makes tiny incisions on your skin and removes the plugs with tweezers and a magnifying glass. Dried cells might be removed beforehand. This is done with a topical exfoliant. The process is simple and you will see results right away.
• Cryotherapy: A dermatologist can also use liquid nitrogen to freeze the milia.
• Chemical peels: This treatment removes the top layer of skin.
• Laser ablation: Your healthcare provider uses a laser to destroy the cysts.
• Curettage: This procedure involves scraping and cauterizing the skin.

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. 

Consider changing your skincare routine. Look for products labeled "oil-free" or "non-comedogenic" which 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.