Folate exposures and risk of colorectal cancer: an umbrella review of meta-analyses of observational studies and randomised controlled trials.

ABSTRACT:

Objectives

To systematically summarise and evaluate the existing evidence of the associations between diverse folate exposures and the risk of colorectal cancer (CRC), while identifying evidence quality.

Design

Umbrella review of meta-analyses.

Data sources

PubMed, Web of Science, Cochrane and Embase were searched from the database inception to March 2024, with an update to 12 October 2025.

Eligibility criteria

We included meta-analyses of randomised controlled trials or observational studies that investigated the associations between folate exposures and CRC or precancerous lesions (ie, adenoma and polyps).

Data extraction and synthesis

For each association, we recalculated the summary effect size with 95% CI using the DerSimonian and Laird random-effec

SUBMITTER: Li T 

PROVIDER: S-EPMC12666042 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature