Acne is the most common skin condition in America, with over 85% of teens--and
many adults, as well--experiencing breakouts at least occasionally.
Acne is linked to the sebaceous glands, which produce sebum (or
oil). These glands are attached to hair follicles (see diagram at
right). Acne occurs when excess sebum, skin cells from a hair follicle's
lining and skin proteins clump together, plugging up the opening
of a follicle so sebum cannot reach the surface of the skin. Plugged
follicles can take the form of either "whiteheads," where
the plugged follicle remains beneath the skin's surface, or "blackheads,"
where the plug in the follicle extends to the skin's surface and
becomes visible.
Once a follicle becomes plugged, it creates an ideal environment
for a common sebum-eating skin bacterium, Propionibacterium acnes (or just P. Acnes), to multiply. This bacterium produces
enzymes and chemicals that irritate and inflame the skin around
a clogged follicle. "Pimples," "breakouts,"
or "zits" are common names for the lesions that result
from this type of skin irritation and inflammation, though doctors
have more precise ways of classifying acne
lesions.
For most people, acne is a generally mild condition. Of course, a pimple
at the wrong time is never desirable, but in truth, there are far
more concerning issues than acne. For some people, however, severe
cases can result in permanent scarring if left untreated.