Every inch of your facial skin contains pores, but the ones you notice are the openings of oil-producing glands, typically ranging from 250 to 500 micrometers wide. Several factors determine whether those openings stay barely visible or become prominent enough to bother you: how much oil your skin produces, your sex, your age, and whether debris has physically stretched the opening over time.
Oil Production Is the Biggest Factor
The single strongest predictor of visible pore size is how much oil your skin pushes out. Your face is covered in tiny glands that produce sebum, a waxy substance that keeps skin moisturized. Each gland empties through a pore. The more sebum a gland produces, the wider the opening needs to be to release it. A large study using multiple regression analysis found that sebum output correlated more strongly with pore size than any other variable measured.
What controls sebum production? Hormones, especially androgens like testosterone and its more potent form, DHT. Your oil glands contain receptors for these hormones and even have the enzymes to convert testosterone into DHT on-site. When androgen levels rise, the glands ramp up oil production. This is why pores often become more noticeable during puberty, when androgen levels surge and sebum output peaks. Growth hormone and IGF-1, which also peak in adolescence, independently stimulate oil production in the glands. In adults with acne, the number of acne lesions, DHT levels, and IGF-1 levels all track together.
Why Men Tend to Have Larger Pores
Biological sex is the second strongest predictor of pore size, after oil output. Men consistently produce more sebum than women. Measurements across multiple studies show the difference clearly: on the forehead, men produce roughly 128 micrograms of sebum per square centimeter compared to about 105 in women. On the cheeks, the gap is even wider, with men averaging around 84 micrograms versus 49 in women. That higher oil volume means larger glands and wider pore openings. A Korean study of 60 subjects found a striking positive correlation between male sex, pore size, and sebum excretion.
Women may notice their pores fluctuate with hormonal shifts during menstrual cycles, pregnancy, or menopause, since estrogen and androgens both influence the oil glands through different receptor pathways.
How Aging Changes Pore Shape
Pores don’t just get bigger with age. They change shape. In younger skin, pores tend to be round. As the supportive proteins in your skin break down over decades, pores become more elongated and oval, sometimes described as “droopy.” This happens because the structural framework around each pore weakens, and the opening sags slightly under gravity.
Researchers have found that conspicuous pores are associated with wrinkle severity and loss of the protein matrix in the deeper layers of skin, suggesting the same process that causes wrinkles also makes pores more visible. Sun exposure accelerates this breakdown. Chronic UV light exposure is a recognized cause of enlarged pores, independent of oil production, because it degrades the proteins that keep skin firm and pore walls taut.
Clogged Pores Stretch Over Time
When dead skin cells and oil accumulate inside a pore, they form a plug. This starts microscopically small, but as more material builds up, the plug physically stretches the walls of the pore. The gradual accumulation of keratin and sebum converts a tiny blockage into a closed comedone (a whitehead). Through continuous distension, the follicular opening expands further, eventually forming an open comedone (a blackhead) with a visibly dilated pore.
This stretching can become semi-permanent. Once the pore wall has been repeatedly dilated by plugs, it loses some of its ability to snap back to its original size, especially in older skin with less elasticity. This is one reason that long-term acne can leave behind noticeably larger pores even after breakouts stop.
Genetics Set Your Baseline
Genetic predisposition is listed alongside sex, aging, and sun exposure as a recognized cause of enlarged pores. Your genes influence how large your oil glands are, how much sebum they produce, and how your skin’s support structure holds up over time. If your parents had visibly large pores, you’re more likely to as well. Ethnicity plays a role too. A multiethnic study comparing Chinese and French women found that individual pore surfaces ranged from 0.06 to 0.16 square millimeters, with similar measurement thresholds across both groups but different distribution patterns.
Pores Don’t Open and Close
A persistent belief holds that steam “opens” pores and cold water “closes” them. This isn’t how pores work. Unlike pores on some other parts of the body, facial pores don’t have muscles wrapped around them that can contract or relax on command. The tiny muscles in your skin (arrector pili muscles) connect to hair follicles and are responsible for goosebumps, but they respond to cold or emotion, not to skincare routines, and they don’t meaningfully change the diameter of the oil gland opening on your face.
What steam and warm water can do is soften the sebum and debris inside a pore, making it easier to clear. Cold water can temporarily reduce slight swelling in surrounding skin, which may make pores appear smaller for a short time. But the pore itself stays the same size.
What Actually Makes Pores Look Smaller
Since the primary driver of visible pores is oil output, anything that reduces sebum accumulation at the surface can make pores less noticeable. Keeping skin clean, using products that dissolve the keratin plugs inside pores, and controlling excess oil all help prevent the physical stretching that makes pores permanently wider. Retinoids increase skin cell turnover and can reduce the buildup that distends pore walls.
Sun protection matters more than most people realize. Because UV damage weakens the structural support around each pore, consistent sunscreen use helps preserve the firmness that keeps pores looking tight. This effect compounds over years, so the benefit isn’t immediately visible but becomes significant with age.
For pores that have already been stretched by years of clogging or sun damage, professional treatments like laser resurfacing or chemical peels can stimulate the skin to rebuild some of its structural proteins, partially tightening the area around the pore. These approaches don’t eliminate pores, but they can reduce their visible diameter by restoring some of the support structure that was lost.