Here’s how often you should wash your hair, according to a dermatologist.

in my late twenties. She took one look at my scalp and said, “You have seborrheic dermatitis. You need to wash your hair more, not less.”

I was stunned. Everything I thought I knew was wrong.

We’ve all heard the myths: Washing too often dries out your hair. Skipping washes trains your scalp to produce less oil. Daily shampooing causes damage. But what does science actually say?

According to dermatologists, the truth is refreshingly simple: There is no universal rule—but for most people, washing 3 to 5 times per week strikes the ideal balance between cleanliness and scalp health. The