What is acne primarily caused by?

Acne is primarily caused by clogged hair follicles, which is why this answer is correct. The formation of acne occurs when hair follicles become blocked due to excess oil (sebum) production, dead skin cells, and sometimes the presence of bacteria. The skin's sebaceous (oil) glands produce sebum, which can mix with dead skin cells and fill the hair follicle. This blockage can lead to inflammation and the development of acne lesions such as pimples, cysts, and nodules.

Understanding the anatomy of the skin is crucial here; the hair follicles are essential components where hair grows and where sebaceous glands open. When these follicles are clogged, they create an environment conducive to bacterial growth, further exacerbating the condition.

Other options relate to skin health but do not directly cause acne. For instance, overproduction of melanin is associated with skin pigmentation issues rather than acne. Excessive sweating, although it can contribute to skin irritation, does not directly lead to clogged follicles. Allergic reactions may result in skin irritations but are not a primary cause of acne. Thus, recognizing the role of clogged hair follicles helps clarify the primary mechanism behind acne formation.