What is seborrhea caused by?

Seborrhea is a condition characterized by an excess secretion of the sebaceous glands, leading to oily or greasy skin. The sebaceous glands produce sebum, which is a natural oil that helps to keep the skin moisturized and serves as a barrier against environmental factors. When these glands overproduce sebum, it can result in conditions such as seborrheic dermatitis, which manifests as red, scaly patches and often occurs on the scalp or face.

The correct choice emphasizes this overproduction of sebum, which can disrupt the normal balance of skin oils and lead to various skin issues. In contrast, the other choices focus on different conditions or factors that do not directly correlate to seborrhea, such as deficiencies, allergic reactions, or infections, which do not primarily lead to an increase in sebum production. Understanding this connection helps in recognizing the underlying causes of skin conditions within the realm of esthetics.