A non-contagious inflammatory skin condition characterized by flaky, white to yellowish scales on various areas of the body, including the scalp, eyebrows, eyelids, ears, and trunk. Seborrheic dermatitis can occur with or without redness. The exact cause of seborrheic dermatitis is unknown, but it may be due to an overproduction of skin oil combined with irritation from a yeast. Factors that might increase the risk of seborrheic dermatitis include family history, stress, fatigue, use of alcohol-containing lotions, skin disorders, obesity, HIV infection, and certain neurologic conditions.