Although I was overweight for most of the 17 years I spent dieting and bingeing, there was a bit of time—a year and a half to be exact—during which my weight loss whittled myself down to bare bones.

Emily Delgado is stuck in the ’80s, ’90s and the early 2000s. A fashionista with an affinity for the past, Delgado created Thin Thrift, her own vintage clothing shop operated through an Instagram page ...