Journal of Public Health and Nursing
Long-Term Effects of Intermittent Fasting on Weight Loss and Body-Weight Maintenance in Adults With Overweight and Obesity: A Systematic Review and Meta-Analysis of Randomized Controlled Trials and Prospective Studies With 12-Month or Longer Follow-Up
By Nasser Hassan Al-swedan, Abdelaziz Elmalky, Miya Yustianingsih and 1 others.
Abstract
Background
Intermittent fasting has gained increasing attention as an alternative to continuous calorie restriction for adults with overweight or obesity. Although short-term weight loss has been widely reported, its long-term effectiveness and ability to maintain weight reduction remain uncertain. This systematic review and meta-analysis evaluated whether intermittent fasting produces sustained weight loss over approximately 12 months or longer and whether it offers an advantage over conventional energy-restriction strategies.
Methods
The review followed PRISMA 2020 principles. Twelve bibliographic databases, multidisciplinary platforms, and trial registries were searched from inception through 28 August 2026 without publication-year restriction. Randomized controlled trials and eligible prospective long-term follow-up studies involving adults aged 18 years or older with overweight or obesity were included. Interventions comprised alternate-day fasting, intermittent energy restriction, 5:2 and 4:3 regimens, and time-restricted eating. The primary outcome was change in body weight at approximately 12 months. Random-effects meta-analysis was used, with active calorie-restriction comparators analyzed separately from usual-care and passive controls. Risk of bias was assessed using Cochrane RoB 2.