Evidence Hub

Alternate-day fasting elicits larger changes in fat mass than time-restricted eating in adults without obesity - A randomized clinical trial

Nina Derron, A. Güntner, I. C. Weber, Julia Braun, I. Ö. Koska, Alaa Othman, Leonie Mönch, A. von Eckardstein et al.

Clinical Nutrition, 2025

26 participants · 8 citations

Abstract

BACKGROUND & AIMS

Intermittent fasting (IF) is a popular nutritional strategy for weight control and improved metabolic health, however it is unclear which type of intermittent fasting is most effective. This randomized trial directly compared short-term alternate-day fasting (ADF) and time-restricted eating (TRE) with controls in adults with overweight or a high normal weight. The aim was to compare the effects of ADF and TRE versus controls regarding whole-body fat mass loss, weight control and cardiometabolic health.

METHODS

In this 4-week, parallel-arm, randomized clinical trial (February 2021-May 2022), participants aged 18-40 years with a body mass index between 23 and 30 kg/m2 were assigned to ADF (alternating fasting and ad libitum eating days), to TRE (eating only between 12:00-20:00), or control (no change in eating times). The primary outcome was change in total fat volume (assessed by whole-body magnetic resonance imaging). Secondary outcomes were subcutaneous and visceral fat mass, body weight, resting metabolic rate, biochemical markers, energy intake, activity energy expenditure and health-related quality of life.

RESULTS

Seventy-six participants (mean [standard deviation (SD)] age, 29.6 [5.6] years; body mass index, 25.8 [2.2] kg/m2; 34 [44 %] female) were randomized to ADF (n = 26), TRE (n = 26), or control (n = 24). Seventy-five participants completed the trial (25 in ADF, 26 in TRE, 24 in control). ADF led to a greater reduction in total fat volume than…

How strong is the evidence?

Evidence Hub reads this as a randomized trial, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 26 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free