What is the main cause of acne vulgaris?

Acne vulgaris primarily results from the overproduction of sebum, which is an oily substance produced by sebaceous glands in the skin. This overproduction can lead to clogged pores, creating an environment conducive to the growth of acne-causing bacteria. When hair follicles become blocked with sebum and dead skin cells, it results in inflammation and the characteristic lesions of acne.

While dietary choices, sun exposure, and genetic factors can contribute to the severity and persistence of acne, they are not the main cause. Diet may influence the condition in some individuals, but it is not universally established as a primary factor. Excessive sun exposure can damage the skin and potentially worsen existing acne but does not initiate its formation. Genetic factors can predispose individuals to acne, affecting sebum production or skin cell turnover, yet the primary mechanism driving acne development remains the overproduction of sebum and the consequent blockage of pores.