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How do sebaceous glands produce oil in mammalian skin?

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A pangolin walks through grass with a blue circle around it and the word endangered written in white across the image. — Integument The pangolin is the only mammal in the world covered in scales.

Sebaceous glands produce oil, known as sebum, through a unique process called holocrine secretion.123

Unlike glands that remain intact during the release of their products, sebaceous glands function by the complete disintegration of their own cells. The process occurs as follows:12

Cell Generation: New cells are continuously produced by cell division around the periphery of the gland's lobes (acini).1
Synthesis: As these cells migrate toward the center of the lobe and the sebaceous duct, they synthesize and accumulate fat globules, causing them to become progressively larger and distorted.1
Disintegration: Upon reaching the duct, the cells undergo complete breakdown, turning into a mixture of lipids—including triglycerides, wax esters, squalene, and cholesterol—and cellular debris.41
Discharge: This resulting mixture is discharged as sebum into the hair follicle and eventually onto the surface of the skin.41

This continuous cycle ensures that the gland is always replenishing its cells to maintain the production of sebum, which helps keep the skin flexible and hydrated.42