Thanks to size-zero models gracing the covers of magazines, billboard ads, commercials, and more, comparing our own bodies to society’s “ideal” one was commonplace in the ’90s and early 2000s.
In its broadest sense, body composition components are muscle, fat, and bone. But you see, muscle is more dense and compact than fat. Meaning, muscle mass occupies less space than fat (aka adipose tissue) in the body. Therefore, someone gaining muscle could experience comparable weight gain as someone who’s increasing their fat percentage, so the difference lies in body composition. Likewise, weight loss could be a positive thing (if you’re making healthy, intentional lifestyle choices to lose fat, i.e., excess adipose stores) or a negative thing (if you’re unintentionally losing muscle, due to inactivity, inadequate protein intake, specific health issues, etc.).