What causes acne?

Dr. Jeanne Morrison, PhD
Family Practitioner

Acne is caused by clogged hair follicles in the skin. Normally, hormones cause sebum, or oil, to be produced in the hair follicle and then released through the opening of the follicle onto the skin's surface. However, when dead skin cells, dried sebum, and bacteria block the opening of the follicle, sebum starts to build up. Bacteria, which are normally found in the hair follicle, grow at an abnormally fast rate in the sebum of the clogged pore. This inflames the skin and causes pimples and cysts.

Contrary to popular belief, greasy foods and dirt do not cause acne. Acne is caused by genetic influences; if your parents had acne, you are more likely to develop it. Hormones, specifically male hormones called androgens, of which testosterone is the best known, also play a major role in acne's development.

At the heart of acne is simple inflammation of the follicle—the small oil-producing area and hair that make up a single pore. The oil gland is called the sebaceous gland and secretes an oily substance called sebum. The oil-producing cells are continually replaced by new cells at the base of the gland, so sebum is actually a combo of both fat and old, dead cells. In a normal follicle, these old cells are brought up to the surface of the skin to shed via the hair shaft. Old cells lining the follicle will also fall from the wall and shed, too. The oil gland helps orchestrate this turnover by keeping the skin well lubricated, so those old cells can move up and out. Problems can arise if something goes wrong and the pores get clogged with gunk, from dead cells and sebum fats to excess bacteria that normally reside in the follicle but in a controlled state.

From The Mind-Beauty Connection: 9 Days to Less Stress, Gorgeous Skin, and a Whole New You by Amy Wechsler.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.