Acne, an inflammatory disease of the skin, is characterized by pimples, blackheads and whiteheads on the skin. It can occur on virtually all parts of the body, though the most common sites on the body where acne manifests are on the face, the neck and other upper parts of the body. An acne incident usually starts with the pimples, with the whiteheads and blackheads commonly coming up soon or later. Acne is commonest among teenagers and young adults, though older people are not completely immune to it.

Acne has a number of causes, and the proper treatment of individual cases of the condition typically calls for an understanding of what could be causing each individual case of acne, as the different causes of acne call for different courses of treatment.

The commonest cause of acne is hormonal change, especially with regard to the hormones referred to as androgens. To understand how androgens cause acne, it is important to appreciate the fact that in the course of their action, androgens tend to (sometimes) cause the oil-producing glands in the skin to produce excessive sebum (which is the skin's natural oil), and should this excessive sebum happen to find the acne causing bacteria, one would be sure to end up seeing all the manifestation of the illness: pimples, blackheads and all. And since most hormonal changes in the body take place during the teenage years and early adulthood years (which are also characterized by the highest levels of almost all hormones), it is not surprising that acne tends to afflict people in these age brackets the most.

From our description of the first and commonest cause of acne, two additional causes have come up, namely bacteria and sebum.

The bacteria responsible for causing acne is called Propionibacterium Acne, which unlike other disease-causing bacteria, is not absolutely linked to poor hygiene, so that you can get afflicted with acne is spite of the best hygienic standards (though good hygiene does go a long way in keeping acne at bay). What happens to cause acne to manifest is that the presence of these bacteria naturally causes the body's white blood cells to spring to action, since the white blood cells are always poised to fight any invasions of the body by pathogens. So what the white blood cells do immediately upon ‘becoming aware' of the presence of acne bacteria is to produce an enzyme to fight the bacteria, with the action of the enzyme (rather than the action of the bacteria as many people mistakenly think) being responsible for the inflammation that is described as acne.

Sebum, on the other hand, is accused of being one of the causes for acne given that excessive amounts of it on the skin cause the removal of dead cells from the skin difficult, making a very attractive place for the acne causing bacteria to thrive, with the bacteria in turn attracting the white blood cells, and the white blood cells in turn causing the enzymatic action which causes the inflammation we refer to as acne.

Poor skin care practices are the fifth major cause of acne. Skin care practices that, for instance, block the skin pores are sure to make an attractive place for the acne bacteria to thrive, with the acne bacteria's presence in turn attracting the white blood cells' ‘ire' causing the enzymatic action which results in the inflammation we refer to as acne.