Acne typically appears on your face, neck, chest, back and shoulders, which are the areas of your skin with the largest number of functional oil glands. Acne can take the following forms:
Three factors contribute to the formation of acne: 1. Build-up of bacteria 2. Irregular shedding of dead skin cells resulting in irritation of the hair follicles of your skin 3. Overproduction of oil (sebum)
Acne occurs when the hair follicles become plugged with oil and dead skin cells. Each follicle is connected to sebaceous glands. These glands secrete an oily substance known as sebum to lubricate your hair and skin. Sebum normally travels up along the hair shafts and then out through the opening of the hair follicle onto the surface of your skin. When your body produces an excess amount of sebum and dead skin cells, the two can accumulate in the hair follicle and solidify as a soft plug. This plug may cause the follicle wall to bulge and produce a whitehead. Or, the plug may be open to the surface and may darken, causing a blackhead. Pustules are raised red spots with a white centre that develop when blocked hair follicles become inflamed or infected. Blockages and inflammation that develop deep inside hair follicles produce lumps beneath the surface of your skin called cysts. Other pores in your skin, which are the openings of the sweat glands onto your skin, aren't normally involved in acne. Contrary to what some people think, foods have little effect on acne. Acne also isn't caused by dirt. In fact, scrubbing the skin too hard or cleansing with harsh soaps or chemicals can cause irritation, which may make acne worse.
Hormonal changes in your body can provoke or aggravate acne. Such changes are common in:
Other risk factors include: