Sebaceous hyperplasia is enlargement of the skin oil glands (sebaceous glands) causing benign small bumps. These harmless bumps often appear soft, yellowish in colour with a cauliflower-like or donut-shaped appearance ranging in size from 2 to 3mm. They usually appear on the forehead and cheeks, where oil glands are plentiful. While it is not a painful condition, lumps may be irritated by shaving, glasses or clothing.
Sebaceous hyperplasia tends to be more common in fair-skinned people who have dealt with oily or combination skin over the years. There is also a genetic component, and it can manifest in people over 40 who have a family history of the condition. Sun damage can also be a factor.