Stephen Pullan, a trichologist at the Philip Kingsley Trichological Clinic in New York, tells Refinery29 that all dandruff doesn't look the same."It can be thought of as dead skin cells shedding off the top layer of the scalp, [which] happens all over the body," he says. "The process can speed up, however, creating visible dandruff, or even worse, [symptoms] such as a bothersome form of flakes that adhere to the hair shaft and can create hair loss."