title: Relationship between body composition changes and changes in physical function and metabolic risk factors in aging.
abstract: OBJECTIVE
  Several body composition changes are known to occur with aging. The purpose of this review is to evaluate recent literature examining body composition changes with aging and how these relate to changes in physical function and metabolic risk.
  
  
  RESULTS
  Cross-sectional and longitudinal studies have observed increases in fat mass and decreases in muscle mass or lean tissue mass in older adults, often in the absence of differences or changes in body weight. Cross-sectional studies have also reported increases in intramyocellular lipid and liver fat in older versus younger adults and related changes in body composition with changes in physical function and metabolic risk, but few longitudinal data are available. Furthermore, most longitudinal studies lack precise methods of assessing body fat distribution and muscle and organ quality, resulting in a lack of detailed and precise information on body composition changes with aging and their relationship to health.
  
  
  CONCLUSIONS
  Research to date has outlined a need for more detailed body composition measurements of aging adults. Absence of change in a total body compartment may mask a change in subcompartments that may impact health. Furthermore, intervention studies to determine ways to maintain body composition are consistent with healthy living throughout the aging process.
authors.affiliation: Department of Nutrition Sciences, Division of Physiology and Metabolism, University of Alabama at Birmingham, Birmingham, AL 35226-3360, USA. mpstonge@uab.edu
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: St-Onge
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000368:Aged; D000375:Aging / Q000502:physiology*; D001823:Body Composition / Q000502:physiology*; D050218:Body Fat Distribution; D004734:Energy Metabolism / Q000502:physiology*; D006801:Humans; D018482:Muscle, Skeletal / Q000378:metabolism; D012307:Risk Factors