Seborrheic dermatitis is one of the most common skin conditions: it can resolve in the first year of life or instead have a chronic relapsing course (and thus recur over the years).
At the root of seborrheic dermatitis is an inflammation of the skin involving the areas of the body richest in pilo sebaceous glands (i.e., very small glands connected to the hair and producing a substance called sebum). This inflammation causes reddening of the skin and the formation of scales, which can be dry or yellowish and greasy.
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