title: A randomized pilot study comparing zero-calorie alternate-day fasting to daily caloric restriction in adults with obesity.
abstract: To evaluate the safety and tolerability of alternate-day fasting (ADF) and to compare changes in weight, body composition, lipids, and insulin sensitivity index (Si) with those produced by a standard weight loss diet, moderate daily caloric restriction (CR).
  
  
  
  Adults with obesity (BMI ≥30 kg/m(2) , age 18-55) were randomized to either zero-calorie ADF (n = 14) or CR (-400 kcal/day, n = 12) for 8 weeks. Outcomes were measured at the end of the 8-week intervention and after 24 weeks of unsupervised follow-up.
  
  
  
  No adverse effects were attributed to ADF, and 93% completed the 8-week ADF protocol. At 8 weeks, ADF achieved a 376 kcal/day greater energy deficit; however, there were no significant between-group differences in change in weight (mean ± SE; ADF -8.2 ± 0.9 kg, CR -7.1 ± 1.0 kg), body composition, lipids, or Si. After 24 weeks of unsupervised follow-up, there were no significant differences in weight regain; however, changes from baseline in % fat mass and lean mass were more favorable in ADF.
  
  
  
  ADF is a safe and tolerable approach to weight loss. ADF produced similar changes in weight, body composition, lipids, and Si at 8 weeks and did not appear to increase risk for weight regain 24 weeks after completing the intervention.
authors: Department of Medicine, Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.|Department of Biostatistics and Informatics, Colorado School of Public Health, Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors: Victoria A
authors: VA
authors: Catenacci
authors: Department of Pediatrics, Children's Hospital Colorado Research Institute, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors: Zhaoxing
authors: Z
authors: Pan
authors: Department of Biostatistics and Informatics, Colorado School of Public Health, Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.|Department of Epidemiology, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors: Danielle
authors: D
authors: Ostendorf
authors: Department of Community and Behavioral Health, Colorado School of Public Health, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors: Sarah
authors: S
authors: Brannon
authors: Kaiser Permanente, Denver, Colorado, USA.
authors: Wendolyn S
authors: WS
authors: Gozansky
authors: Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA.|Department of Neuroscience, the Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors: Mark P
authors: MP
authors: Mattson
authors: Laboratory of Clinical Investigation, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, USA.
authors: Bronwen
authors: B
authors: Martin
authors: Department of Medicine, Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.|Department of Biostatistics and Informatics, Colorado School of Public Health, Anschutz Health and Wellness Center, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors: Paul S
authors: PS
authors: MacLean
authors: Department of Medicine, Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.|Department of Medicine, Division of Geriatrics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors: Edward L
authors: EL
authors: Melanson
authors: Department of Medicine, Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.|Kaiser Permanente, Denver, Colorado, USA.
authors: William
authors: W
authors: Troy Donahoo
mesh_terms: D000328:Adult; D001823:Body Composition; D001835:Body Weight; D031204:Caloric Restriction; D004038:Diet, Reducing / Q000379:methods; D002149:Energy Intake; D005215:Fasting; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000178:diet therapy*; D010865:Pilot Projects; D016896:Treatment Outcome; D015431:Weight Loss