The material that emerges when you squeeze a blackhead is a dense plug made mostly of sebum (the oily substance your skin naturally produces) and dead skin cells bound together by a protein called keratin. It often comes out as a small, firm, worm-like strand with a dark tip and a lighter, yellowish or off-white body. The plug can also contain bacteria, fungi, and even microscopic mites that naturally inhabit your pores. What surprises most people is that the dark color at the surface is not dirt at all, but the result of a chemical reaction between the plug’s contents and the air.
The Two Main Ingredients
Your skin is covered in tiny structures called sebaceous glands, which sit at the base of hair follicles and pump out sebum, a waxy mixture of lipids that keeps your skin and hair moisturized. Sebum production is a normal, continuous process. Problems start when the opening of a follicle becomes partially blocked by an accumulation of dead skin cells that would normally shed on their own. Instead of sloughing off, these cells stick together with the help of keratin, a tough structural protein, and form a plug that traps sebum beneath it.1Oxford Academic (British Journal of Dermatology). Homeostasis of the sebaceous gland and mechanisms of acne pathogenesis
So when you press on a blackhead, what slides out is essentially a cast of the inside of the pore: a column of hardened sebum and compacted keratin. Professional dermatologists describe this extracted material plainly as “keratinous contents.”2Journal of Cutaneous and Aesthetic Surgery. Surgical pearl: Dissecting forceps wrapped with adhesive tape for atraumatic periorbital senile comedone extraction The texture can range from soft and paste-like to surprisingly solid, depending on how long the plug has been sitting there. A fresh, shallow blackhead yields a softer, more oily mass. One that has been lodged in the pore for weeks or months can feel almost waxy or gritty when squeezed between your fingers.
Why the Tip Is Black
The name “blackhead” is misleading in one important way: it implies the pore is clogged with dirt. It is not. The plug’s dark cap forms because the pore is open to the air. When sebum and melanin (the same pigment that colors your skin and hair) sit exposed at the surface, they undergo oxidation. This is essentially the same kind of chemical browning you see when you slice an apple and leave it on the counter. The oxygen in air reacts with the lipids and melanin in the plug, turning them dark brown or black.
Contrast this with a whitehead, where the pore opening is sealed over by a thin layer of skin. The same mixture of sebum and dead cells sits underneath, but because it never contacts air, it stays pale. The composition of what is inside the two is nearly identical; the only real difference is whether the plug has an open or closed surface. That is why dermatologists classify both as types of comedones, differing mainly in whether the follicle’s opening is dilated (open comedone, or blackhead) or covered (closed comedone, or whitehead).3PubMed Central. An update on the role of the sebaceous gland in the pathogenesis of acne
The Microorganisms Inside the Plug
Sebum and keratin are not the only things packed into a blackhead. Your pores are home to a thriving community of microorganisms, and these get trapped inside the plug as it forms. Research examining the contents of follicles has identified large populations of three main groups living in them: Propionibacterium (now often called Cutibacterium acnes), Staphylococcus species, and the yeast-like fungus Malassezia.4PubMed. Microorganisms inhabiting follicular contents of facial acne are not only Propionibacterium but also Malassezia spp. These organisms are part of the normal skin microbiome and are present even on healthy skin without any acne at all.
That said, the environment inside a plugged pore is especially hospitable to these microbes. The trapped sebum serves as a rich food source, and the low-oxygen conditions deep in the follicle suit anaerobic bacteria like C. acnes particularly well. Studies comparing acne-affected skin with clear skin have found high bacterial numbers on both, but the skin around active blackheads, papules, and pustules tends to harbor especially dense colonies.5PubMed. Acne vulgaris: an investigation into the number of anaerobic diphtheroids and members of the Micrococcaceae in normal and acne skin When you squeeze out a blackhead plug, you are expelling some of this bacterial load along with the oily, keratinous core.
Tiny mites called Demodex also live in human hair follicles, particularly on the face. These are microscopic arthropods, and nearly every adult carries them. They feed on sebum and generally cause no harm, though in some people an overpopulation of them can trigger inflammation. Whether a given blackhead plug carries Demodex along with it depends on the pore’s location and the person’s skin, but the mites are a normal part of the follicular ecosystem.
Sebaceous Filaments Are Not Blackheads
Many people who think they have a face full of blackheads are actually looking at sebaceous filaments. These are normal structures present in every pore, especially visible on the nose, chin, and inner cheeks. A sebaceous filament is the thin, thread-like lining of sebum that naturally coats the inside of a follicle as oil moves toward the surface. When you squeeze one, a tiny, pale, hair-thin strand of sebum comes out, and the filament refills within about 30 days because the gland keeps producing oil.
The key differences are visual. A true blackhead has a distinctly dark, raised, or slightly bumpy tip, and when extracted, the plug is noticeably larger and firmer. A sebaceous filament looks like a small, flat, grayish or yellowish dot. There is no real “plug” to remove, just the normal flow of oil through the pore. Squeezing sebaceous filaments is essentially futile: they come back quickly and squeezing them repeatedly can enlarge pores and irritate the skin. If the dots on your nose are uniform in size, evenly distributed, and the same color as each other, they are almost certainly filaments rather than blackheads.
Why Squeezing Causes Problems
Even when you are dealing with a genuine blackhead, manual squeezing carries real risks. The most immediate one is that you can rupture the follicle wall below the skin surface. Instead of the plug exiting cleanly through the pore opening, pressure forces some of its contents deeper into the surrounding tissue. Sebum, keratin, and the bacteria trapped inside are now loose in the dermis, where they trigger an immune response. The result is a red, swollen, painful bump that is far worse than the blackhead was, and which may leave a dark mark or scar as it heals.
Fingernails and unsterilized tools also introduce new bacteria to the area. The skin around the nose and the center of the face drains into veins that connect to the brain’s venous network, which is why dermatologists are especially cautious about aggressive squeezing in the area sometimes called the “danger triangle” between the bridge of the nose and the corners of the mouth. Serious infections from casual squeezing are rare, but they do happen, and they tend to happen in exactly this zone.
Repeated squeezing can also physically stretch the pore opening over time. A pore that has been dilated by frequent manual extraction becomes more visible and may refill with sebum and dead cells faster than a pore left alone. This creates a frustrating cycle: the blackhead seems to come back faster and look more prominent, which prompts more squeezing, which stretches the pore further.
Why Blackheads Form in Certain Areas
The nose, chin, forehead, and inner cheeks are blackhead hotspots for a simple reason: these areas have the highest concentration of sebaceous glands on the body. The so-called T-zone (forehead, nose, and chin) can have several hundred glands per square centimeter, while the skin on your arms or legs has far fewer. More glands mean more sebum, and more sebum means more opportunities for a pore to become clogged.
Hormones play a significant role in determining how much sebum your glands produce. Androgens, which spike during puberty and fluctuate throughout adult life, directly stimulate sebaceous glands to produce more oil. This is why blackheads often first appear in the early teenage years and can flare during hormonal shifts like menstrual cycles, pregnancy, or polycystic ovary syndrome. The sebaceous gland itself contains the enzyme machinery needed to convert circulating hormones into their active forms locally in the skin, so even modest hormonal changes can have outsized effects on oil production in specific areas.3PubMed Central. An update on the role of the sebaceous gland in the pathogenesis of acne
Individual pore size, which is largely genetic, also matters. People with naturally larger pores produce and accumulate more sebum per follicle, making visible plugs more likely. No amount of skincare will shrink a pore below its genetic baseline, though keeping the pore lining clear of excess keratin can make pores appear less prominent.
How to Clear Blackheads Without Squeezing
The most effective at-home approach targets the two ingredients of the plug: the excess keratin blocking the pore and the sebum trapped beneath it. Salicylic acid, a common ingredient in over-the-counter acne washes and serums, works by disrupting the bonds between dead skin cells at the pore’s surface. Rather than dissolving the cells themselves, it loosens the junctions holding them together, which helps the plug break apart and exit on its own.6PubMed Central. Salicylic acid as a peeling agent: a comprehensive review Because salicylic acid is oil-soluble, it can penetrate into the pore rather than just sitting on the skin’s surface, which is why it tends to work better for blackheads than water-soluble exfoliants.
Retinoids, which are vitamin A derivatives available both over the counter (adapalene) and by prescription (tretinoin, tazarotene), take a different approach. They speed up the turnover of skin cells lining the follicle, preventing dead cells from accumulating into a plug in the first place. Topical retinoids have a direct comedolytic effect, meaning they actively break down existing comedones while also preventing new ones from forming.7PubMed. The integral role of topical and oral retinoids in the early treatment of acne They do not kill bacteria directly, so their benefit is purely structural: keeping the pore lining thin and the opening clear.
For stubborn or deep blackheads, professional extraction by a dermatologist or trained esthetician is safer than doing it yourself. The standard technique involves using a comedone extractor, a small metal loop that applies even, downward pressure around the pore opening to push the plug out cleanly. For closed comedones, a tiny nick with a sterile needle opens the surface first. When done properly, this causes minimal tissue injury and little to no bleeding.2Journal of Cutaneous and Aesthetic Surgery. Surgical pearl: Dissecting forceps wrapped with adhesive tape for atraumatic periorbital senile comedone extraction The key advantage over finger-squeezing is controlled, even pressure that is far less likely to rupture the follicle wall.
What the Color and Texture Tell You
People who extract blackheads at home often try to read meaning into what comes out. Here is what the visual cues actually indicate:
- Dark tip, pale body: A classic open comedone. The dark cap is oxidized sebum and melanin; the lighter core beneath has been shielded from air. This is the standard blackhead.
- Entirely pale or white: Either a closed comedone (whitehead) or a sebaceous filament. If it was flat and barely visible before you squeezed, it was probably a filament.
- Gritty or sand-like texture: A plug that has been in the pore for a long time. Sebum can harden considerably with age, and some long-standing comedones develop a granular feel from compacted keratin.
- Liquid or pus-like: The comedone has likely progressed to an inflammatory lesion. The presence of pus means your immune system has responded to the bacteria inside, and what you are now dealing with is closer to a pustule than a simple blackhead. Squeezing at this stage significantly increases the risk of scarring.
A common question is whether the plug will “grow back” after extraction. The answer, frustratingly, is often yes. Removing the plug does not change the underlying conditions that created it. The sebaceous gland continues producing oil, and if dead skin cells continue to accumulate at the pore opening, a new plug forms in the same spot. This is why dermatologists emphasize ongoing topical treatment with retinoids or salicylic acid rather than one-time extraction. The goal is to prevent plugs from forming, not to keep pulling them out after the fact.
Blackheads That Are Not Really Acne
Not every dark-tipped bump on the skin is an ordinary acne blackhead. Older adults sometimes develop clusters of large, prominent open comedones around the eyes and temples, a condition called solar or senile comedones. These are caused by long-term sun damage that weakens the skin around follicles and allows them to dilate, rather than by the hormonal oil overproduction that drives teenage acne. The plugs look and feel similar when extracted, but the treatment approach is different because the root cause is structural skin damage rather than excess sebum.
Dilated pore of Winer is another look-alike: a single, unusually large open comedone, sometimes several millimeters across, that contains a large keratinous plug. It is benign and essentially a cosmetic concern, but it can be mistaken for something more serious. The plug that comes out of a dilated pore of Winer is the same sebum-and-keratin material, just on a larger scale than a typical blackhead.
Chloracne, caused by exposure to certain industrial chemicals like dioxins, also produces severe comedones, sometimes across the entire body. The plugs in chloracne contain the same basic ingredients, but the condition is driven by chemical toxicity rather than normal skin physiology, and it can persist for years even after exposure ends. These examples illustrate that while the material inside a blackhead is always fundamentally the same mixture, the reasons it accumulates can vary enormously from person to person.