Does the weight loss efficacy of alternate day fasting differ according to sex and menopausal status?

Abstract

Background and aims: This study examined if the weight loss and metabolic benefits of alternate day fasting (ADF) varies according to sex and menopausal status in adults with obesity.

Methods and results: This secondary analysis pooled the data of men and women (n = 75) who participated in three 12-week ADF studies (500 kcal fast day; alternated with an ad libitum intake feast day). Body weight decreased in premenopausal women (-4.6 ± 3.2%), postmenopausal women (-6.5 ± 3.2%) and men (-6.2 ± 4.4%) (main effect of time, P < 0.001), with no difference between groups (no group × time interaction). Energy intake on fast days was higher than prescribed in all groups (∼400-500 excess kcal consumed), with no differences between groups. Fat mass, lean mass, fasting insulin, and insulin resistance, and blood pressure decreased similarly in all groups (main effect of time, P < 0.05 for all comparisons). LDL cholesterol decreased more in postmenopausal versus premenopausal women (group × time interaction, P = 0.01). Fasting glucose, HDL cholesterol, and triglycerides remained unchanged in all groups.

Conclusion: These findings suggest that the weight loss and metabolic benefits of ADF do not generally vary according to sex or menopausal status in adults with obesity.

Trial registration: Clinicaltrials.gov, NCT00960505; NCT03528317.

Keywords: Intermittent fasting; Menopausal status; Metabolic disease; Obesity; Sex differences; Weight loss.

Conflict of interest statement

Declaration of Competing Interest KAV has a consulting relationship with the sponsor of the research, Nestle Health Sciences. The other authors have no conflicts of interest to disclose.

Copyright © 2020 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Figures

Figure 1.

Subject flow chart: Pooled analysis

Figure 2.. Weight loss and dietary adherence

Values are expressed as means ± SD. A. Body weight significantly decreased from baseline in premenopausal women, postmenopausal women and men by week 12 (main effect of time, P < 0.001), with no difference between groups (no group × time interaction). B. Actual energy intake on the fast day was significantly greater (P < 0.01) than prescribed for premenopausal women, postmenopausal women, and men, with no difference between groups.