Blackheads form when a hair follicle gets clogged with a mix of oil and dead skin cells, and that plug stays open at the skin’s surface. Unlike whiteheads, where the pore closes over the clog, a blackhead’s opening is wide enough for air to reach the trapped material. That exposure to air is what creates the dark color. It’s not dirt, and it’s not a sign of poor hygiene.
What’s Actually Happening Inside the Pore
Your skin has tiny oil glands attached to almost every hair follicle. These glands produce sebum, a waxy oil that keeps your skin moisturized and flexible. At the same time, your skin constantly sheds dead cells from the lining of each pore. Normally, sebum carries those dead cells up and out of the follicle without any trouble.
Problems start when the body produces too much sebum, or when dead skin cells don’t shed properly. Instead of flowing out, the oil and skin cells clump together and form a plug inside the follicle. If the skin over that plug stays intact and sealed, you get a whitehead (a closed comedone). If the plug stretches the pore open, exposing its surface to air, you get a blackhead (an open comedone).
The dark color comes from a chemical reaction, not from trapped grime. Melanin, the same pigment that gives your skin and hair their color, is present in those dead skin cells. When melanin contacts oxygen in the air, it oxidizes and turns dark brown or black. So a blackhead is essentially a tiny deposit of oxidized pigment sitting at the opening of a pore.
Why Your Body Overproduces Oil
Hormones are the biggest driver. Androgens, a group of hormones that includes testosterone, directly control how much oil your sebaceous glands produce. These glands have androgen receptors on their cells, and when androgens bind to those receptors, the glands ramp up oil production and physically enlarge. This is why blackheads and acne so often appear during puberty: androgen levels surge, and oil glands that were relatively dormant since infancy suddenly grow and start pumping out sebum.
The hormonal connection is strong enough that people born without functioning androgen receptors don’t produce sebum and don’t develop acne at all. On the other end of the spectrum, any hormonal shift that raises androgen activity, such as puberty, menstrual cycles, polycystic ovary syndrome, or certain medications, can trigger a noticeable increase in oiliness and clogged pores.
More than half of 13-year-olds already have some form of acne, with girls affected slightly more often than boys at that age (62% versus 45% in one large study from the Netherlands). But blackheads aren’t just a teenage problem. Roughly 40% of adults between 30 and 39 still deal with acne, often concentrated along the nose, chin, and forehead where oil glands are densest.
Other Factors That Contribute
Hormones set the stage, but several other things can tip the balance toward clogged pores:
- Skincare and cosmetic products. Some ingredients are more likely to block pores than others. Cosmetic chemists use a comedogenic scale from 0 to 5 to rate how pore-clogging an ingredient is. Ingredients like isopropyl palmitate score high on this scale. That said, concentration matters: an ingredient rated as highly comedogenic at full strength may cause no issues at low percentages in a finished product. “Noncomedogenic” on a label is a helpful starting point, but it’s not a guarantee.
- Friction and pressure. Tight clothing, helmets, phone screens pressed against your face, and habitually resting your chin on your hand can all push oil and debris deeper into follicles or prevent them from clearing naturally.
- Overwashing. Scrubbing your face aggressively or washing too frequently can strip the skin’s surface and trigger your oil glands to compensate by producing even more sebum. Acne flare-ups cannot be traced to dirt or poor hygiene, and harsh cleansing often makes things worse rather than better.
- Humidity and sweat. Hot, humid environments increase sweating and surface oil, which can mix with dead cells and accelerate pore clogging, especially if sweat sits on the skin for extended periods after exercise.
Why Squeezing Makes Things Worse
It’s tempting to squeeze a visible blackhead, but pressing on the skin can push the clog deeper into the follicle, rupture the follicle wall beneath the surface, and spread bacteria into surrounding tissue. That kind of damage can turn a simple blackhead into an inflamed, painful pimple or even a deeper cyst. Repeated squeezing also raises the risk of scarring and can introduce new bacteria from your fingers.
Blackheads can progress into more severe forms of acne on their own, but picking and squeezing accelerates that process. If a blackhead is bothering you, extraction tools used by a trained professional are far less likely to cause damage than your fingertips.
How Blackheads Are Treated
The most effective over-the-counter ingredient for blackheads is salicylic acid, a type of beta-hydroxy acid. What makes it particularly useful is that it dissolves in oil. While water-based exfoliants work mainly on the skin’s surface, salicylic acid can actually penetrate into the oily interior of a clogged pore, break down the mix of sebum and dead cells, and help the plug clear out. You’ll find it in cleansers, toners, and leave-on treatments, typically at concentrations between 0.5% and 2%.
Retinoids, which are vitamin A derivatives available both over the counter and by prescription, work differently. They speed up cell turnover in the lining of the pore, preventing dead cells from accumulating and forming plugs in the first place. Retinoids are especially useful for people who get blackheads repeatedly in the same areas, since they address the root cause rather than just dissolving existing clogs.
For persistent blackheads that don’t respond to topical products, professional extraction and chemical peels can clear out deeper plugs. These approaches work best when combined with a daily routine that keeps oil production managed and pores clear, since blackheads will simply return if the underlying factors haven’t changed. Choosing noncomedogenic moisturizers and sunscreens, washing gently (not aggressively) after sweating, and using a leave-on salicylic acid product on blackhead-prone areas are the most practical everyday steps for keeping pores open.