Body composition

Body composition measurement with dual energy X-ray absorptiometry (DEXA) is used increasingly for a variety of clinical and research applications.

Total body scans using DEXA give accurate and precise measurements of body composition, including bone mineral content (BMC), bone mineral density (BMD), lean tissue mass, fat tissue mass, and fractional contribution of fat.

[5] DEXA measurements are highly reproducible if the same type of machine is used,[6] making them excellent for monitoring pharmaceutical therapy, nutritional or exercise intervention, sports training, and other body composition altering programs.

DEXA exams provide both total body and up to 14 regional (trunk, individual arms & legs, android, gynoid, etc.)

[8] Potassium 40 is a naturally occurring radioactive isotope found in intracellular water, but is not present in stored triglycerides (fat).

By controlling hydration status or performing multiple impedance measurements, it is possible to estimate body fat and other variables.

InBody developed the world's first 8-point tactile electrode system in 1996, a direct segmental analysis method that measures the impedance of five torsos using multiple frequencies.

[10] Recent advancements such as 8-point electrodes, multi-frequency measurements, and Direct Segmental Analysis,[11] have improved the accuracy of BIA machines.

[12] BIA machines have found acceptance in medical, fitness, and wellness space owing to their ease-of-use, portability, quick measurements, and cost efficiency.

AURA Devices developed and launched a number of wearable bioimpedance trackers, including the first smart strap for Apple Watch that tracks body fat, muscles, lean mass, water levels, etc.

Initially, BVI technology employed white light scanning machines to measure an individual's body shape.

It can be done in nine steps: A common skin fold method is by using gun style calipers to measure the thickness of subcutaneous fat in multiple places on the body.

Ultrasound has also been used to measure subcutaneous fat thickness, and by using multiple points an estimation of body composition can be made.

[16] [17] Ultrasonography has many advantages over CT scan and MRI as it is non-invasive and doesn't utilize ionizing radiation, making it more accessible to special populations.

The methods above are each valid and notable in providing a measurement that can be used to determine the "true body composition" of the tested individual.

[23] The ideal percent of body mass which should be fat depends on an individual's sex, age, and physical activity.