Causes

Acne starts in the skin's sebaceous glands. These glands secrete an oily substance called sebum. The sebum normally travels through a tiny hair follicle from the gland to the skin's surface. Sometimes the sebum becomes trapped, mixing with dead skin cells and bacteria. This causes a clogged pore called a comedo (plural: comedones).

Pimple

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Blackheads are comedones that reach the skin's surface. Whiteheads are comedones that stay beneath the surface of the skin. Small red bumps, pimples, and cysts may also develop.

The main causes of acne include:

• Changes in levels of male hormones called androgens
• Increased sebum production
• Changes inside the hair follicle
• Bacteria

Risk Factors

A risk factor is something that increases your chances of getting a disease or condition.

• Age: between 12-24 years old
• Race: Caucasian
• Changes in hormone levels, such as during:
  • Puberty
  • Pregnancy
  • Before a menstrual period
• Stress
• Certain medications (such as androgens, lithium , and barbiturates)