Your body is covered with millions of hair follicles that pump out protective oils, but it takes just one clog to create a dreaded blemish. Bacteria, dead skin, oil, and white blood cells that gave their lives fighting infection combine into a repulsive white pus that erupts when you give the pimple a squeeze (which you should never do, unless you want to memorialize that zit with a scar).
Pores become clogged if there is too much sebum and too many dead skin cells. Bacteria can then get trapped inside the pores and multiply. This causes swelling and redness — the start of acne.
If a pore gets clogged up and closes but bulges out from the skin, you’re left with a whitehead. If a pore gets clogged up but stays open, the top surface can darken and you’re left with a blackhead. Sometimes the wall of the pore opens, allowing sebum, bacteria, and dead skin cells to make their way under the skin — and you’re left with a small, red bump called a pimple (sometimes pimples have a pus-filled top from the body’s reaction to the bacterial infection).
Clogged pores that open up very deep in the skin can cause nodules, which are infected lumps or cysts that are bigger than pimples and can be painful. Occasionally, large cysts that seem like acne may be boils caused by a staph infection.
Picture Credit : Google