What causes acne?
No one factor causes acne. Acne occurs when sebaceous (oil) glands attached to the hair follicles are stimulated at the time of puberty or due to other hormonal changes. Sebum (oil) is a natural substance that lubricates and protects the skin. Associated with increased oil production is a change in the manner in which the skin cells mature, predisposing them to plug the follicular pore. The plug can appear as a whitehead if it is covered by a thin layer of skin, or if exposed to the air, the darker exposed portion of the plug is called a “blackhead.” The plugged hair follicle gradually enlarges, producing a bump. As the follicle enlarges, the wall may rupture, allowing irritating substances and normal skin bacteria access into the deeper layers of the skin, ultimately producing inflammation. Inflammation near the skin’s surface produces a pustule; deeper inflammation results in a papule (a pimple); if the inflammation is deeper still, it forms a cyst.
Here are some factors that don’t usually play a role in acne:
Food: Parents often tell teens to avoid pizza, greasy and fried foods, and junk food. While these foods may not be good for overall health, they don’t play an important causal role in acne. Although some recent studies have implicated a high-carbohydrate diet, milk, and pure chocolate in aggravating acne, these findings are far from established. Dirt: Blackheads are oxidized oil, not dirt. Sweat does not cause acne and is produced by entirely separate glands in the skin. On the other hand, excessive washing can dry and irritate the skin. Stress: Some people get so upset by their pimples that they pick at them and make them last longer. Stress, however, does not play much of a direct role in causing acne.