Milia are caused by dead skin cells that get trapped beneath the surface of your skin instead of shedding normally. When old cells don’t slough off, new skin grows over them, and the trapped cells harden into tiny, firm white cysts. These pinhead-sized bumps appear most often on the face, particularly around the eyes, cheeks, and nose, and unlike acne, they have no opening to the surface, which is why you can’t squeeze them out.
How Dead Skin Gets Trapped
Your skin constantly replaces itself. Old cells on the surface die and fall away so newer cells can take their place. Milia form when that turnover process stalls. The dead cells cluster together, become encased in a pocket of skin, and harden into a ball of a protein called keratin. Because the cyst sits just under the outer layer of skin, it shows through as a small, pearly white or yellowish bump that feels firm to the touch.
This can happen for no obvious reason at all. Dermatologists call these “primary milia,” and they’re by far the most common type in adults. There’s no single trigger you can point to. Some people are simply more prone to sluggish cell turnover in certain areas of the face, especially the delicate skin around the eyes where the tissue is thinner and pores are smaller.
Skin Damage and Secondary Milia
When milia appear after some kind of injury or irritation to the skin, they’re classified as secondary (or traumatic) milia. The healing process can disrupt normal cell shedding, trapping debris under the new skin that forms during repair. Common triggers include:
- Sun damage. Chronic UV exposure thickens the outer layer of skin over time, making it harder for dead cells to shed. This is one reason milia often cluster on sun-exposed areas of the face.
- Burns or blisters. Thermal burns, chemical burns, and blistering skin conditions can all leave behind milia as the skin heals.
- Skin procedures. Treatments like dermabrasion, laser resurfacing, and aggressive chemical peels can trigger milia during the recovery phase. The new skin that forms over treated areas sometimes seals dead cells underneath.
- Rashes and inflammatory skin conditions. Conditions that cause prolonged irritation or blistering on the face can lead to secondary milia once the inflammation resolves.
Secondary milia tend to appear in clusters right at the site of the original damage, which can help distinguish them from primary milia that pop up more randomly.
Skincare Products That Contribute
Heavy, occlusive skincare products are a well-known contributor, especially when applied around the eyes. Ingredients like petrolatum, mineral oil, lanolin, and thick synthetic waxes create a physical seal over the skin that can trap dead cells underneath. Even heavy botanical oils applied thickly overnight can play a role. The eye area is particularly vulnerable because the skin there is so thin and the pores are extremely small, so it takes very little to block the natural shedding process.
If you’re prone to milia, switching to lighter, non-comedogenic moisturizers and eye creams can make a noticeable difference. This doesn’t mean you need to avoid all moisturizing products. It means choosing formulas that hydrate without forming a heavy barrier, especially in the areas where your milia tend to appear.
Why Babies Get Milia
Nearly half of healthy newborns develop milia, usually on the nose and cheeks. In infants, the cause is straightforward: their skin is brand new and still learning to shed cells efficiently. These tiny white bumps, sometimes called milk spots, are completely harmless and typically resolve on their own within a few weeks without any treatment. They don’t indicate a skin problem or allergic reaction, and they don’t need to be picked at or treated with products.
What Milia Are Not
Milia are often mistaken for whiteheads, but they’re fundamentally different. A whitehead is a clogged pore filled with oil and bacteria. Milia are keratin-filled cysts with no connection to a pore opening, which is why they don’t respond to acne treatments and can’t be popped. They also look different from syringomas, which are small sweat gland growths that tend to be yellowish or skin-toned rather than white, and often appear in clusters beneath the lower eyelids. If your bumps are soft, yellowish, and flat, they may be cholesterol deposits rather than milia.
How to Address and Prevent Them
Because milia sit beneath the skin’s surface, they won’t go away with washing or scrubbing. Gentle chemical exfoliation can help prevent new ones from forming by keeping cell turnover active. Cleansers and peels containing salicylic acid or glycolic acid help dissolve the bonds between dead cells so they shed more easily instead of accumulating. Citric acid is another option in the same category.
Topical retinoids (vitamin A derivatives) are one of the more effective tools for both treating existing milia and preventing new ones. Retinoids speed up cell turnover, which directly addresses the sluggish shedding that causes milia to form in the first place. If you’re using a retinoid or its milder over-the-counter form, retinol, apply it once daily to clean, dry skin. Start slowly, since these products can cause irritation when your skin is adjusting.
For stubborn milia that won’t budge, a dermatologist can extract them in a quick office visit using a sterile needle or small blade to open the skin and release the cyst. This is safe and leaves minimal scarring when done professionally. Attempting extraction at home risks infection and scarring, particularly around the delicate eye area where most facial milia appear.