The skin has minute glands called sebaceous glands that open into the hair follicle. These glands secrete an oily substance called sebum, which empties into the skin surface through the hair follicle. During puberty, the male sex hormones which are normally present both in males and females are on the rise and they activate the sebaceous glands to increase in size, which in turn leads to an increase in the secretion of sebum. Secondly, the cells are shed more rapidly and they stick together, plugging the opening of the hair follicle, resulting in ‘whiteheads’. The pigment melanin in the whiteheads when exposed to air, forms blackheads. Thirdly, bacteria especially the’ propionibacterium acne’ in number and add to the formation of acne. When the follicle gets clogged, its wall ruptures. The sebum, bacteria and dead cells escape into the surrounding tissue and lead to the formation of the more severe form of acne in the form of pustules, nodules, abscesses, and cysts.