title: Effect of calorie restriction on energy expenditure in overweight and obese adult women.
abstract: Energy expenditure (EE) may decrease in subjects on hypocaloric diets, in amounts that exceed body mass loss, favoring weight regain.
  
  
  OBJECTIVE
  To verify if a short-term caloric restriction lowers Resting Energy Expenditure (REE) and Total Energy Expenditure (TEE) more than predicted by changes in body composition, and if this reduction of EE is related with compliance to the diet.
  
  
  METHODS
  Twenty-two women aged 23-44 years with a body mass index (BMI) of 25-32 kg/m2, underwent a three-month calorie restriction treatment (20 kcal/kg initial weight) and were encouraged to increase their physical activity. At the beginning and end of the intervention, body composition (DEXA), REE, Physical Activity Energy Expenditure (PAEE) and TEE were assessed, through a combination of indirect calorimetry and actigraphy. Participants, who lost more or equal than 5% of their initial weight were considered compliant with the diet.
  
  
  RESULTS
  In the compliant group, REE decreased, when expressed in absolute numbers or when adjusted by fat free mass (FFM) [-164 ± 168 kcal/day (10,6%) and -4,3 ± 4,6 kcal/kg FFM (10,5%)]. This decline was significantly greater than that observed in the non-compliant group [-6,2 ± 1.42 Kcal/day (0.16%) and -0,5 ± 3,4/Kg FFM (0.96%)]. FFM did not change in any of the two groups. At baseline, there was a significant correlation between FFM and REE (r = 0, 56 p < 0,05), which was lost at the end of the intervention.
  
  
  CONCLUSIONS
  Compliant women showed a significant reduction in both absolute and adjusted REE, which together with the loss of correlation between REE and FFM at the end of the intervention suggests a metabolic adaptation.
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. teresajimenezjaime@gmail.com.
authors.forename: Teresa
authors.initials: T
authors.lastname: Jiménez Jaime
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. lleiva@inta.uchile.cl.
authors.forename: Laura
authors.initials: L
authors.lastname: Leiva Balich
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. lleiva@inta.uchile.cl.
authors.forename: Gladys
authors.initials: G
authors.lastname: Barrera Acevedo
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. lleiva@inta.uchile.cl.
authors.forename: María Pía
authors.initials: MP
authors.lastname: de la Maza Cave
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. lleiva@inta.uchile.cl.
authors.forename: Sandra
authors.initials: S
authors.lastname: Hirsch Birn
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. lleiva@inta.uchile.cl.
authors.forename: Sandra
authors.initials: S
authors.lastname: Henríquez Parada
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. lleiva@inta.uchile.cl.
authors.forename: Juan
authors.initials: J
authors.lastname: Rodríguez Silva
authors.affiliation: Instituto de Nutrición y Tecnología de los Alimentos. Universidad de Chile, Chile.. lleiva@inta.uchile.cl.
authors.forename: Daniel
authors.initials: D
authors.lastname: Bunout Barnett
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D001823:Body Composition; D015992:Body Mass Index; D031204:Caloric Restriction; D038441:Diet, Mediterranean; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy* / Q000378:metabolism*; D050177:Overweight / Q000178:diet therapy* / Q000378:metabolism*; D010349:Patient Compliance; D055815:Young Adult