Elsevier

Advances in Nutrition

Volume 7, Issue 4, July 2016, Pages 690-705
Advances in Nutrition

Could Intermittent Energy Restriction and Intermittent Fasting Reduce Rates of Cancer in Obese, Overweight, and Normal-Weight Subjects? A Summary of Evidence

https://doi.org/10.3945/an.115.011767Get rights and content
Under an Elsevier user license
open archive

Abstract

Animal studies and human observational data link energy restriction (ER) to reduced rates of carcinogenesis. Most of these studies have involved continuous energy restriction (CER), but there is increasing public and scientific interest in the potential health and anticancer effects of intermittent energy restriction (IER) or intermittent fasting (IF), which comprise periods of marked ER or total fasting interspersed with periods of normal eating. This review summarizes animal studies that assessed tumor rates with IER and IF compared with CER or ad libitum feed consumption. The relevance of these animal data to human cancer is also considered by summarizing available human studies of the effects of IER or IF compared with CER on cancer biomarkers in obese, overweight, and normal-weight subjects. IER regimens that include periods of ER alternating with ad libitum feed consumption for 1, 2, or 3 wk have been reported to be superior to CER in reducing tumor rates in most spontaneous mice tumor models. Limited human data from short-term studies (≤6 mo) in overweight and obese subjects have shown that IER can lead to greater improvements in insulin sensitivity (homeostasis model assessment) than can CER, with comparable reductions in adipokines and inflammatory markers and minor changes in the insulin-like growth factor axis. There are currently no data comparing IER or IF with CER in normal-weight subjects. The benefits of IER in these short-term trials are of interest, but not sufficient evidence to recommend the use of IER above CER. Longer-term human studies of adherence to and efficacy and safety of IER are required in obese and overweight subjects, as well as normal-weight subjects.

intermittent energy restriction
intermittent fasting
cancer
obese
normal weight

Abbreviations used

ADER
alternate-day energy restriction
ADF
alternate-day fasting
CER
continuous energy restriction
CRP
C-reactive protein
CVD
cardiovascular disease
ER
energy restriction
IER
intermittent energy restriction
IF
intermittent fasting
IGF
insulin-like growth factor
IGFBP
insulin-like growth factor binding protein
MMTV
mouse mammary tumor virus
mTOR
mammalian target of rapamycin
NIA
National Institute on Aging
p53
tumor protein 53
ROS
reactive oxygen species
sirt
sirtuin

Cited by (0)

The authors reported no funding received for this article.

Author disclosures: MN Harvie and T Howell have written 3 self-help books for the public to follow intermittent diets. All author proceeds are paid directly to the charity Genesis Breast Cancer Prevention Appeal (registered charity no. 1109839) to fund breast cancer research.