Acne vulgaris is a skin disorder that affects the oil glands in the skin. Sebum is a substance produced by the sebaceous gland or the oil gland which is a part of the philobaceous unit – the unit which falls prey to the bacteria that cause acne. Sebum clogs up skin pores and makes them susceptible to bacteria.

Propionibacterium acnes, a bacterium that is a normal inhabitant of our skin is the primary cause of acne. The normal reaction of the body to the presence of bacteria is to send an army of white blood cells to the affected area. In the war between the white blood cells and Propionibacterium acnes an enzyme is produced. This enzyme damages the walls of the follicle and all the irritants present in the affected follicle pour into the dermis. As a result there is a certain amount of inflammation which we commonly refer to as pimples or zits.

During the teenage years the body experiences a surge in hormone production. These hormonal changes result in increased production of sebum. But not all teenagers fall prey to acne. The reason given for this is heredity. Children whose parents have suffered from acne are sure to get it. The use of certain medicines also causes acne for some. The cause here is not the medicine involved but the reaction produced within the body.

Hormonal changes that occur during pregnancy can also bring on acne in any of its forms. Acne attacks are also seen in women who use birth control pills. Acne is usually seen in such women either when they start or stop taking birth control pills as that is when a hormonal imbalance occurs. Excessive use of greasy makeup is also suspected to be a cause of acne. This is because the grease clogs up the pores of the philobaceous unit and the acne causing bacteria get the right conditions to flourish in.