* Genetics: Some people are simply predisposed to producing more oil in their scalp.
* Skin type: Oily skin can lead to oily hair.
* Hair care routine: Using the wrong shampoo or conditioner, not washing hair frequently enough, or using too much styling product can all contribute to greasy hair.
* Medical conditions: Some medical conditions can affect sebum production.
* Diet: A diet high in fatty foods can lead to increased sebum production.
* Stress: Stress can also affect sebum production.
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