Magazine images show perfectly poreless skin on models' noses and cheeks, but under the cosmetics and photographic manipulation, they probably have the same tiny indentations on the oiliest parts of their faces that others do. You might mistake these small dimples for the blackheads they resemble, but chances are most of them are not blemishes, but naturally occurring sebaceous filaments.
Your skin contains thousands of minuscule glands that produce a waxy, oily material called sebum. If you have an oily complexion, your sebaceous glands are responsible. Overactive sebaceous glands arise from genetic predisposition to an oily skin and from hormonal activity. Under normal circumstances, your sebaceous glands keep your skin moisturized and supple, but when they become clogged, they can also become reservoirs for infectious bacteria.
Sebum that builds up and solidifies into a plug within a pore forms a blackhead. Blackheads also consist of shed skin cells in addition to sebum. The naturally whitish sebum turns brown or black when it oxidizes, giving the blackhead its characteristic dark color. If your dermatologist presses the blackhead from your skin, you can see how the wormlike plug has a darker cap toward the end that was once exposed to the air. Don't try to express a blackhead from your skin yourself -- you risk scarring from squeezing.
If you look closely at the tip of your nose, you might see tiny dots that superficially resemble blackheads. While these marks are also the tips of columnar structures that fill your pores, these are not products of infection. They're sebaceous filaments, naturally occurring hairlike formations that channel the flow of sebum along the lining of the pore in which they lie. While this may not sound appealing, it's a natural phenomenon on almost everyone's skin.
A blackhead is a solitary eruption on the skin, while sebaceous filaments form an even, random pattern throughout an oilier area of your skin such as your nose or chin. Blackheads tend to be larger and darker while sebaceous filaments have a grayish or tan hue rather than a blackhead's charcoal color. Sebaceous filaments typically feel smooth to the touch, unlike a large blackhead which might have a raised rim around the recessed, plugged pore. Blackheads may accompany whiteheads, the raised white pimples that indicate an acne breakout. Sebaceous filaments occur on virtually every adult's nose and bear no association with acne.