A Randomized Pilot Study Comparing Zero-Calorie Alternate-Day Fasting to Daily Caloric Restriction in Adults With Obesity

Obesity (Silver Spring). 2016 Sep;24(9):1874-83. doi: 10.1002/oby.21581.

Abstract

Objective: 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).

Methods: 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.

Results: 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.

Conclusions: 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.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Body Composition
  • Body Weight
  • Caloric Restriction*
  • Diet, Reducing / methods
  • Energy Intake
  • Fasting*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Obesity / diet therapy*
  • Pilot Projects
  • Treatment Outcome
  • Weight Loss