Tinea versicolor is very common, and though it’s annoying, it’s fortunately not dangerous. “It’s a skin condition caused by a specific kind of yeast called malassezia,” New York City dermatologist Janet Prystowsky, M.D. tells SELF. Malassezia is something that exists naturally on the skin, and tinea versicolor is an overgrowth of this yeast. Malassezia is also the cause for other skin conditions like dandruff and psoriasis. And while it can’t be spread by skin-on-skin contact (meaning it’s not contagious), it’s hard to determine just what causes tinea versicolor, says Schultz.

The rash typically begins to appear on the upper arms, chest, and back. The yeast infection causes skin to change color, typically in small one-eighth or quarter-inch spots. The skin can turn pinker, lighter, or darker. “Light-colored skin tends to get darker spots, while dark-colored skin seems to [turn] lighter,” says Schultz. In some cases of tinea versicolor (like mine) skin turns white because the fungus produces azelaic acid, which bleaches and lightens the skin. And once the infection has passed, it could take a few months for the skin to get back its proper pigment, explains Prystowsky.