The association of dietary insulin load and index with the risk of cancer and cancer mortality: a systematic review and meta-analysis

Farshad Teymoori; Ebrahim Mokhtari; Alireza Bahrami; Hossein Farhadnejad; Mina Azadi; Milad Nazarzadeh; Mohammadreza Vafa

doi:10.1007/s40200-022-01013-3

The association of dietary insulin load and index with the risk of cancer and cancer mortality: a systematic review and meta-analysis

J Diabetes Metab Disord. 2022 Mar 1;21(1):1105-1118. doi: 10.1007/s40200-022-01013-3. eCollection 2022 Jun.

Authors

Farshad Teymoori^{1

2}, Ebrahim Mokhtari¹, Alireza Bahrami³, Hossein Farhadnejad¹, Mina Azadi², Milad Nazarzadeh⁴, Mohammadreza Vafa^{2

5}

Affiliations

¹ Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
² Department of Nutrition, Faculty of Public Health, Iran University of Medical Sciences, Tehran, Iran.
³ Department of Clinical Nutrition and Dietetics, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
⁴ The George Institute for Global Health, University of Oxford, Oxford, UK.
⁵ Department of Nutrition, Faculty of Public Health, Iran University of Medical Sciences, Shahid Hemmat Highway, P.O.BOX: 1449614535, Tehran, Iran.

Abstract

Purpose: Insulin levels play an important role in cancer development. However, the link between an insulinogenic diet and cancer is still unclear. Therefore, we performed a systematic review with meta-analysis to investigate the association between dietary insulin index (II) and load (IL) with cancer risk and mortality.

Methods: A comprehensive search between electronic databases (Web of Science, PubMed/Medline, Scopus, and Google Scholar) was conducted to identify relevant studies up to January 2022. The relative risks (RR) and Odds ratios (OR) were extracted from eligible studies, and meta-analysis was performed to calculate the pooled effect size.

Result: 12 papers including 14 studies (10 cohorts and 4 case-control) were included for the meta-analysis. Among them, 10 studies reported effect size for the risk of cancer, and 4 studies reported effect size for cancer mortality. We observed no significant association between II and IL with cancer overall (RR_II: 1.03, 95%CI: 0.91-1.17, RR_IL: 1.16, 95%CI: 0.94-1.42) and in cohort studies, however, in case-control studies was related with higher odds of cancer (OR_II: 2.30, 95%CI: 1.21-4.38, OR_IL: 2.57, 95%CI: 1.64-4.02). Higher II and IL scores were associated with the increased risk of total (RR_II: 1.29, 95%CI: 1.02-1.63) and (RR_IL: 1.39, 95%CI: 1.06-1.83) and colorectal cancer mortality (RR_II: 1.29, 95%CI: 1.13-1.48) and (RR_IL: 1.37, 95%CI: 1.18-1.60).

Conclusion: Higher dietary II and IL were not associated with cancer risk in overall and cohort studies, whereas related with a higher risk of cancer in case-control studies. We observed a significant positive relation of II and IL with cancer mortality, especially CRC mortality.

Supplementary information: The online version contains supplementary material available at 10.1007/s40200-022-01013-3.

Keywords: Cancer; Cancer mortality; Insulin index; Insulin load; Meta-analysis.

Publication types

Review