What causes pimples?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
A pimple forms when a hair follicle becomes blocked by a mixture of skin oil and dead skin cells that are trying to shed onto the surface of the skin.  As oil continues to be produced, it backs up inside the follicle.  Any bacteria that may be present start to reproduce.  The body’s immune system attacks the bacteria, forming inflammation and pus. Watch the animation to see how this happens.

Pimples occur when pores become clogged with oil. Your skin naturally produces oil to keep it from drying out, but a surge of hormones can cause skin to produce too much oil. A pimple is formed when the oil mixes with dead skin cells and forms a "plug" that blocks the pore. If the plug is exposed to air it turns black, forming a blackhead. If the pore is completely blocked, a whitehead forms. Bacteria thrive on the excess oil inside the blocked pore, and when the skin tries to fight the bacteria, the pore swells and turns red. Teenagers and pregnant women are particularly vulnerable to hormonal changes and pimples.

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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.