Acne appears when a pore in your skin clogs. Normally, dead skin cells rise to surface of the pore, and the body sheds the cells. When the body makes oil, called sebum (see-bum), the dead skin cells can stick together inside the pore. Instead of rising to the surface, the cells and oil become trapped inside the pore, causing it to clog.
If the pore remains open, the clogged material that is exposed to air will turn black over time, coining the phrase ‘blackhead’. This is a result of a chemical reaction. Blackheads are not dirt. If the pore pinches at the top and air is not allowed in, a small white lesions will appear, named a ‘whitehead’. If inflammation occurs around the clogged pore, a red ‘pimple’, nodules or cyst may form.
Sometimes bacteria that live on our skin, p. acnes, also get inside the clogged pore. Inside the pore, the bacteria have a perfect environment for multiplying very quickly. Heavy loads of bacteria can cause lesions to become more inflamed. If the inflammation goes deep into the skin, an acne cyst or nodule appears.
Men and women both produce hormones called androgens. Androgens stimulate oil glands to produce more oil. These increase oil production and can increase the likelihood of follicles becoming clogged.
Overall, four main factors cause acne:
- Excess oil production
- Hair follicles clogged by oil and dead skin cells
- Excess activity of a type of hormone (androgens)