What is fat mass?

Fat mass describes how much adipose (fat) tissue is in your body. It's measured in pounds or kilograms.

Tracking fat mass over time is a great way to see fat loss progress when following a weight loss program. When doing calorie-restricted dieting, sometimes body fat percentage will not change significantly because of simultaneous fat and muscle loss - this is where tracking fat mass in addition to body fat percentage can be helpful to show overall progress.