Purpose of review: In this review methods to measure the content and distribution of body fat or adipose tissue in humans are examined. The review particularly emphasizes methods to characterize regional fat distribution and ectopic fat (fat contained within other tissues) including specific applications and implications of region-specific or tissue-specific fat content.
Recent findings: Recent novel applications of body composition methods, including in-vivo imaging modalities, magnetic resonance spectroscopy techniques, and direct measurement of extracted tissue have advanced our understanding of many health related issues including obesity, type 2 diabetes mellitus, progressive muscle weakness in aging and lipodystrophy. In particular, the accumulation of lipid within muscle and liver has received increased attention because of its association with metabolic dysregulation or impaired muscle function.
Summary: Methods to quantify total body fat content in humans have provided considerable insight into obesity and related disorders, the aging process and its associated changes in function, and response to intervention. However, these methods have typically not been able to identify fat contained within specific regions of the body or within specific tissue. Direct quantification of fat distribution and fat within tissue in humans have been accomplished through in-vivo imaging techniques as well as invasive histological and biochemical approaches, and have advanced our understanding of many structure-function relationships. Further queries about human health and disease will undoubtedly lead to refinement of these methods and innovation of new body composition methodologies.