Glycemic load, but not glycemic index, is associated with an increased risk of ovarian cancer: A systematic review and meta‐analysis

The association between glycemic index (GI),glycemic load (GL) and ovarian cancer risk remains unclear. Carbohydrate intake promotes insulin secretion, leading to cell proliferation and invasion. We hypothesized that high GI and GL intake may increase ovarian cancer risk. Therefore, we conducted a meta-analysis after systematically searching PubMed, Embase, Web of Science, and Cochrane Library from inception to December 2022. Fixed- or random-effect models calculated the pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs). Subgroup, sensitivity, publication bias analysis, and dose-response analysis were performed. Nine original studies were included, involving 4716 cases and 119,960 controls. No significant association was observed between GI or GL and ovarian cancer risk (GI: RR = 1.02 [95% CI, 0.83-1.26]; GL: RR = 1.11 [95% CI, 0.84-1.47]). Subgroup analysis suggested the results were not significantly modified by any group. Sensitivity analysis identified the sources of heterogeneity. No publication bias was observed. A linear positive dose-response relationship was observed between dietary GL and ovarian cancer risk after removing heterogeneous sources (RR = 1.11 [95% CI, 1.05-1.17], I2 = 32.9%, P = .23 at 50 U/d; RR = 1.04 [95% CI, 1.02-1.07], I2 = 19.1%, P = .29 at 20 U/d). These outcomes suggest that high dietary GL, but not GI, is associated with significantly increased ovarian cancer risk. Thus, sufficient intake of a low dietary GL is important for reducing ovarian cancer risk.