title: Body Composition Changes After Very-Low-Calorie Ketogenic Diet in Obesity Evaluated by 3 Standardized Methods.
abstract: Common concerns when using low-calorie diets as a treatment for obesity are the reduction in fat-free mass, mostly muscular mass, that occurs together with the fat mass (FM) loss, and determining the best methodologies to evaluate body composition changes.
  
  
  
  This study aimed to evaluate the very-low-calorie ketogenic (VLCK) diet-induced changes in body composition of obese patients and to compare 3 different methodologies used to evaluate those changes.
  
  
  
  Twenty obese patients followed a VLCK diet for 4 months. Body composition assessment was performed by dual-energy X-ray absorptiometry (DXA), multifrequency bioelectrical impedance (MF-BIA), and air displacement plethysmography (ADP) techniques. Muscular strength was also assessed. Measurements were performed at 4 points matched with the ketotic phases (basal, maximum ketosis, ketosis declining, and out of ketosis).
  
  
  
  After 4 months the VLCK diet induced a -20.2 ± 4.5 kg weight loss, at expenses of reductions in fat mass (FM) of -16.5 ± 5.1 kg (DXA), -18.2 ± 5.8 kg (MF-BIA), and -17.7 ± 9.9 kg (ADP). A substantial decrease was also observed in the visceral FM. The mild but marked reduction in fat-free mass occurred at maximum ketosis, primarily as a result of changes in total body water, and was recovered thereafter. No changes in muscle strength were observed. A strong correlation was evidenced between the 3 methods of assessing body composition.
  
  
  
  The VLCK diet-induced weight loss was mainly at the expense of FM and visceral mass; muscle mass and strength were preserved. Of the 3 body composition techniques used, the MF-BIA method seems more convenient in the clinical setting.
authors.affiliation: Division of Endocrinology, Department of Medicine, and.
authors.forename: Diego
authors.initials: D
authors.lastname: Gomez-Arbelaez
authors.affiliation: Division of Endocrinology, Complejo Hospitalario Universitario de Ferrol and Coruña University, 15405 Ferrol, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Bellido
authors.affiliation: Division of Endocrinology, Department of Medicine, and.|Centro de Investigacion Biomedica en Red de Fisiopatologia de la Obesidad y Nutricion (CIBERobn), Instituto Salud Carlos III, 15706 Santiago de Compostela, Spain.
authors.forename: Ana I
authors.initials: AI
authors.lastname: Castro
authors.affiliation: Division of Endocrinology, Department of Medicine, and.
authors.forename: Lucia
authors.initials: L
authors.lastname: Ordoñez-Mayan
authors.affiliation: Family Medicine, Sanitary Area of Ferrol, 15405 Ferrol, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Carreira
authors.affiliation: Intensive Care Division, Complejo Hospitalario Universitario de Santiago, 15706 Santiago de Compostela, Spain.
authors.forename: Cristobal
authors.initials: C
authors.lastname: Galban
authors.affiliation: Division of Endocrinology, Department of Medicine, and.|Centro de Investigacion Biomedica en Red de Fisiopatologia de la Obesidad y Nutricion (CIBERobn), Instituto Salud Carlos III, 15706 Santiago de Compostela, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Martinez-Olmos
authors.affiliation: Division of Endocrinology, Department of Medicine, and.|Centro de Investigacion Biomedica en Red de Fisiopatologia de la Obesidad y Nutricion (CIBERobn), Instituto Salud Carlos III, 15706 Santiago de Compostela, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Crujeiras
authors.affiliation: Medical Department PronoKal Group, 08009 Barcelona, Spain; and.
authors.forename: Ignacio
authors.initials: I
authors.lastname: Sajoux
authors.affiliation: Division of Endocrinology, Department of Medicine, and.|Centro de Investigacion Biomedica en Red de Fisiopatologia de la Obesidad y Nutricion (CIBERobn), Instituto Salud Carlos III, 15706 Santiago de Compostela, Spain.
authors.forename: Felipe F
authors.initials: FF
authors.lastname: Casanueva
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods; D000273:Adipose Tissue / Q000473:pathology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000886:Anthropometry / Q000379:methods; D001823:Body Composition / Q000502:physiology*; D001834:Body Water / Q000502:physiology; D031204:Caloric Restriction; D055423:Diet, Ketogenic; D017097:Electric Impedance; D006801:Humans; D007662:Ketosis / Q000503:physiopathology; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology; D009765:Obesity / Q000178:diet therapy* / Q000503:physiopathology; D010991:Plethysmography / Q000379:methods; D011446:Prospective Studies; D015431:Weight Loss / Q000502:physiology; D055815:Young Adult