Use of dual-energy x-ray absorptiometry in body-composition studies: not yet a “gold standard”

The advent of dual-energy x-ray absorptiometry (DEXA) has greatly improved the precision and accuracy of bone-mineral density determinations in research and in clinical practice (1). Because the current generation of DEXA machines can also identify soft tissue and categorize it as fat or lean, there has been a great deal of interest in using DEXA for measurement of these compartments as well. At several conferences we have now heard the conclusion that DEXA is a ‘ ‘gold standard’ ‘ for body-composition research involving noncalcified tissues, and not solely for bone-density research. We suggest that caution be used before DEXA be adopted uncritically for this purpose.