title: Body composition: what's new?
abstract: OBJECTIVE
  Body mass index has been shown to be an imprecise measurement of fat-free and fat mass, and provides no information if weight changes occur as a result of a decrease in fat-free mass or an increase in fat mass.
  
  
  RESULTS
  Non-invasive body composition methods (i.e. bioelectrical impedance analysis, air displacement plethysmography) can now be used to monitor fat-free and fat mass with weight gain and loss, and during aging. This review discusses body composition measurements in terms of ethnic differences, physical activity, and age, and the limitations of bedside techniques in obesity and abnormal hydration status.
  
  
  CONCLUSIONS
  An assessment of the fat-free and fat mass provides valuable information about changes in body composition with weight gain or loss and physical activity, and during aging. Non-invasive bedside techniques can now be used to evaluate the nutritional status of healthy and ill individuals.
authors.affiliation: Clinical Nutrition, Geneva University Hospital, 1211 Geneva 14, Switzerland.
authors.forename: Ursula G
authors.initials: UG
authors.lastname: Kyle
authors.forename: Laurence
authors.initials: L
authors.lastname: Genton
authors.forename: Claude
authors.initials: C
authors.lastname: Pichard
mesh_terms: D000273:Adipose Tissue / Q000502:physiology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001823:Body Composition / Q000502:physiology*; D015992:Body Mass Index; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged