There’s nothing richer than clean, healthy pores—and like other elements of appearance, it’s common for people to stress over their size. The smaller the pores, the clearer your skin appears. And in many cases, size does matter: enlarged pores, for starters, can indicate clogging and/or oil and bacteria buildup.

So what is the “need to know” on pores—those pesky complexion-dotting nuisances we wish we could airbrush away, magazine-style? Here are 5 facts about pores and pore size that will help you understand and treat your skin a bit better.

1. Pores are just glorified hair follicles

Pores are simply the opening of hair follicles, which extend down further through several layers of skin. Each follicle/pore contains or has the ability to grow one shaft of hair, whether that hair is visible or not. Each of us have about 5 million hair follicles, so the amount of pores we fixate on is relatively tiny in proportion to the rest.

Each pore contains its own sebaceous gland, which produces oil. It’s no wonder, then, that pores get clogged with oil and enlarged so frequently.

2. Pore size is genetic

You may have your ancestors to blame or thank for the state of your pores, because pore size is largely determined by your family tree. People who have inherited naturally oily skin are likely to have larger pores because they are more actively releasing oil through wider openings.

This isn’t all bad—in fact large pores (and the oil that comes with them) can counteract the physical toll of aging and wrinkling. It’s why people of Asian descent, for example, tend to have large pores and show less extreme signs of aging.

3. Sun + time = larger pores

Speaking of age, your years alive correlate with pore size too. As we age, our collagen breaks down, causing skin to lose its elasticity with the passing years. As the skin relaxes, pores dilate; we lose the firmness of youth and our pores get more visible. The sagging of the skin stretches pores open into “tear” shapes.

Years upon years of fun in the sun will also, with time, expands your pores. Sun damage leads to inflammation, thickening skin cells. Scorched cells pool around a pores’ edges, making them appear even larger.

4. Bad habits, bad pores

Another reason for large pores? You may have some bad habits that are hurting your skin. Smoking is the big one, here, since inhaling nicotine on the regular dries out your skin, shrinking the blood vessels that deliver oxygen and nourishment. This deprives your skin of important nutrients and speeds the aging process.

A bad diet, lack of proper hydration, affinity for tanning beds, and face-washing neglect also qualify as not-so-great, pore-expanding habits you might want to consider kicking, pronto.

5. You can’t reduce pore size, but you can minimize appearance

It’s not necessarily a bad thing to have large pores, especially since oil secretion can be great for skin, providing a natural layer of protection and moisture. Even so, the best looking complexions don’t emphasize skin follicles, but minimize them.

You can’t actually reduce the size of your pores, because your oil glands will remain what they are genetically. But there’s a lot you can do to make them appear smaller and prevent their expansion. For starters, take care of your skin by exfoliating regularly, wearing sunscreen consistently, staying healthy, smoke-free, and hydrated, and blotting excess oil. Simply washing your face with warm water, then cold water to tighten up the pores can make a big difference.

There are also various procedures and products that can help minimize the appearance of pores. Look for products with charcoal and clay, which draw out impurities, or other pore-minimizing serums and face masks.