The Scientist: Debra Jaliman, M.D., a practicing dermatologist in New York City, American Academy of Dermatology Spokesperson and author of “Skin Rules.”

The Answer: No. Your pores have a genetically determined size, and you can’t get ‘em smaller than that. But there are tons of reasons your pores might have expanded over the years, and thatyou can undo.

Everything You Need to Know About Pores

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Let’s start at the beginning. Different parts of your face have differently sized pores. The ones on your nose are the largest, followed by the forehead and chin. Pores on the cheeks are smaller yet, and the ones around the periphery of the face are the smallest. Some people naturally have pores so tiny you couldn’t find them with a magnifying glass, while other people’s pores are easy to spot with the naked eye. Generally speaking, blondes and redheads have smaller pores than brunettes.

Whatever their size to begin with, when your pores get clogged they stretch out and look bigger. If you have acne, for example, dead skin cells can’t exfoliate properly, so they build up in your pores and enlarge them. Sun damage can also cause your pores to expand by weakening collagen fibers, the structural support system that keeps skin firm.

The most effective way to get pores back to their natural diameter is laser treatment, which removes the top layers of skin. A pore is shaped like an ice cream cone; as you work your way down from the opening it gets smaller. Light peels and microdermabrasion achieve similar ends through different means, and a basic facial will help clean out gunk.

The next-best options include Retin-A or over-the-counter retinol and salicylic acid, which have been shown to clear and narrow pores. These are the ingredients to look for in any product that claims to be “pore-refining.”

The best treatments are also the best courses of prevention. To keep your pores from getting big again, protect your skin from the sun, wear non-comedogenic makeup and keep up a good skincare regimen. To pump up your face-washing routine, use a sonic cleansing system daily and an exfoliating scrub (once a week in the winter, twice a week in the summer) to get rid of dead skin cells.

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