title: Measuring the impact of weight cycling on body composition: a methodological challenge.
abstract: OBJECTIVE
  The impact of weight cycling on body composition and metabolic risk remains controversial. Very few studies, however, meet the methodological requirements to analyze and normalize changes in body composition with weight loss and regain.
  
  
  RESULTS
  Methodological drawbacks that limit the interpretation of results are as follows:first, a small and only partial weight regain, second, the choice of an obese study population who experiences only small changes in fat-free mass, third, a lack of adjustment for the age-related decline in fat-free mass when examining elderly people and fourth, a lack of validity and precision of the body composition method that are important in a nonstable condition of weight loss and for measuring small changes in body composition. Normalization of changes in fat and lean mass for baseline body composition and measurement of fat and lean tissue distribution lead to further insights into the etiology and consequences of weight cycling.
  
  
  CONCLUSIONS
  Current evidence does not support an adverse effect of weight cycling on body composition. By contrast, severe weight loss in normal-weight people that comprises a large loss of lean mass may shift the partitioning toward a transient higher regain in total and abdominal fat mass.
authors.affiliation: aInstitute of Nutritional Medicine, University of Hohenheim, Stuttgart bInstitute of Human Nutrition and Food Science, Christian-Albrechts-University of Kiel, Keil, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Bosy-Westphal
authors.forename: Manfred J
authors.initials: MJ
authors.lastname: Müller
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D001823:Body Composition / Q000502:physiology*; D001825:Body Fluid Compartments / Q000378:metabolism*; D004734:Energy Metabolism; D006801:Humans; D018482:Muscle, Skeletal / Q000378:metabolism*; D009765:Obesity / Q000378:metabolism; D015430:Weight Gain / Q000502:physiology*; D015431:Weight Loss / Q000502:physiology*