The body is composed of fat and fat-free components, such as muscle, bone, and water. Each component plays a critical role in the health of the body. Fat Mass (FM) is the total amount of fat in the body. The ideal amount of fat for minimal disease risk is 23%-31% of total body weight in women.

Fat mass consists of the following types of fat:

  • Subcutaneous Fat, also called Subcutaneous Adipose Tissue (SAT), is located directly beneath the skin. Subcutaneous fat serves as insulation against outside cold.

  • Visceral Fat, also called Visceral Adipose Tissue (VAT), is located deeper within the body. Visceral fat serves as a cushion between organs. Omental and mesenteric fat (in the abdomen) are examples of visceral fat.

Fat-Free Mass (FFM), also called Lean Body Mass (LBM), is the total amount of nonfat (lean) parts of the body. It consists of approximately 73% water, 20% protein, 6% minerals, and 1% ash.