The Effects of Intermittent Energy Restriction on Indices of Cardiometabolic Health

Abstract

Intermittent energy restriction (IER) has become the subject of considerable scientific interest as a potential dietary approach for weight-loss and improving cardiometabolic health. This approach involves intermittent periods of total or partial energy restriction (ER) alternated with non-restricted intake, and has been studied in rodent and human populations. This review aims to provide an overview of the IER literature to date, with a specific focus on its effects on cardiometabolic health indices in rodents and humans. Current evidence from studies in rodents and humans suggests that IER is capable of promoting weight-loss and/or favourably influencing an array of cardiometabolic health indices, with equal or greater efficacy than conventional continuous ER approaches. Putative mechanisms include the effects of IER on adipose tissue physiology, stress resistance and fat distribution within visceral and intra-hepatic sites. However, a large proportion of this mechanistic evidence is limited to indirect observations and/or has come from rodent studies requiring translation into humans. Furthermore, whilst there is some indication that total IER and the array of partial IER protocols which have been developed may elicit distinct biological effects, our knowledge around this is limited as only a small number of rodent studies have directly addressed this. Ultimately, whilst much remains to be learned about IER, including its mechanisms of action and long-term efficacy, the positive findings to date serve to highlight promising avenues for future research.