What is the main characteristic of seborrhea?

The main characteristic of seborrhea is excessive sebum secretion. This condition is often associated with the sebaceous glands, which are responsible for producing oil (sebum) that helps to keep the skin lubricated and protected. When seborrhea occurs, there is an overproduction of this oil, which can lead to greasy skin and hair, as well as potential issues like dandruff or seborrheic dermatitis.

Dry, scaly skin, excessive sweating, and pustule formation do not define seborrhea. While some individuals may experience flaky skin due to associated conditions or environmental factors, the hallmark of seborrhea is that the skin appears oily rather than dry. Excessive sweating is unrelated to seborrhea, as it concerns the eccrine or apocrine sweat glands, and pustule formation typically indicates a different inflammatory or infectious process, such as acne. Hence, excessive sebum secretion is the definitive feature that characterizes seborrhea.