Indications for Body Composition
What specific conditions are body composition measurements useful for?
- Accurately assess lean and fat mass in overweight individuals: Excessive weight and obesity are major health problems in most western societies. Conventional assessments, including weight and body mass index (BMI), are unable to distinguish between muscle mass and fat mass. This is particularly important in progress assessment where subjects have been undertaking exercise programs which increase muscle mass at the same time as decreasing fat mass. DXA can reliably distinguish between muscle mass and fat mass and is a useful tool in assessing overweight or obese individuals. In addition DXA can assess visceral adipose tissue (VAT) which is a marker for risk of diabetes, heart disease and stroke.
- Monitoring exercise program. DXA is more useful than underwater weighing, bioelectrical impedance or skinfold (calipers) measurement, and uses significantly less radiation than CT scanning. DXA Body composition provides the best solution for people wanting highly accurate body composition information to assist with their fitness training or weight-loss program. Individuals may benefit from a DXA scan to measure whole body and central body composition if they are starting an exercise program.
- Assessment of underweight or anorexic individuals. Anorexia nervosa and severely underweight subjects are at high risk of a number of medical complications including osteoporosis and heart disease. Management is best undertaken by medical practitioners experienced in this field with the assistance of a skilled dietician. DXA body composition is a valuable tool to monitor progress of this serious condition.
- Muscle wasting conditions: Cancer, HIV, malabsorption. HIV and some cancers can cause significant loss of weight or changes in body composition. A number of published studies indicate body composition variables are predictive of clinically relevant survival differences although the role of DXA in routine management of these conditions remains under evaluation.