Effects of Fasting on Chemotherapy Treatment Response: A Systematic Review of Current Evidence and Suggestions for the Design of Future Clinical Trials

Abstract

Fasting associated with chemotherapy could improve the efficacy of anticancer treatments without increasing their adverse effects. We conducted a systematic review following the PRISMA Statement to summarize the evidence on the effects of fasting on treatment response of adults undergoing chemotherapy and make suggestions for the design of future clinical trials The search was performed on CENTRAL, PubMed/MEDLINE, LILACS and Embase. Randomized and non-randomized clinical trials evaluating the effects of fasting (above 12 h, at anytime) on treatment response of adult cancer patients undergoing chemotherapy were included. The risk of bias assessment was conducted in accordance with the Cochrane Handbook. Literature search retrieved 1393 citations and three studies were included in the review. All studies had as an intervention fasting of at least 24 h, before chemotherapy. Two studies showed that immediately after chemotherapy, damage to healthy cells was increased, however after 48 and 72 h, of fasting there was a decrease on damage magnitude. There was no difference in chemotherapy-related adverse events between intervention and control groups. All studies presented two or more criteria with a high risk of bias. Fasting of at least 24 h, appears to be safe and showed some beneficial effects on chemotherapy toxicity, that could be further investigated, however studies presented heterogeneous samples and protocols. We highlight the need and provide recommendations for well-designed randomized clinical trials that evaluate the effect of fasting on chemotherapy-related adverse events. This systematic review was registered on PROSPERO as CRD42019120071.

Disclosure Statement

No potential conflict of interest was reported by the authors.

Author Contribution Statement

Author contributions. J.F.K. and E.H.S.C. conducted the search strategy. J.F.K, E.H.S.C., E.H. and C.Q.C. assessed eligibility criteria. J.F.K and E.H.S.C. performed the data extraction. E.H.S.C., C.Q.C., E.I.R. and V.B.P. assessed risk of bias. J.F.K., E.H.S.C., C.Q.C., V.B.P., E.H. and E.I.R. performed analyses and GRADE assessment. All authors contributed significantly to the work’s conception, design, interpretation, and writing in a manner sufficient to establish ownership of the intellectual content. All authors read and approved the version of the manuscript submitted.