Dietary inflammatory index and cardiovascular risk and mortality: an updated systematic review and meta-analysis

Background Cardiovascular diseases (CVDs) are the leading cause of death globally, and chronic inflammation is pivotal in CVDs development. Pro-inflammatory diets may exacerbate inflammation and thus increase CVDs risk. The Dietary Inflammatory Index (DII) is a validated measure of the inflammatory potential of diet. This updated systematic review and meta-analysis was conducted to clarify the association between DII and CVDs incidence and mortality. Methods A comprehensive search was conducted in Pub Med, Web of Science, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI) until February 2025. Study quality was assessed using the Newcastle-Ottawa Scale ( N OS). Risk ratios (HR) and 95% confidence intervals (CI) were pooled using Review Manager 5.4, with subgroup analyses performed. Sensitivity and publication bias analyses were conducted using Stata 18.0. Results Thirty cohort studies (NOS ≥7) from nine countries, involving 669,205 participants, were included. Compared with the lowest DII category, the highest category was associated with increased risks of CVD incidence [HR = 1.23, 95% CI (1.14–1.33); I 2 = 54%] and mortality [HR = 1.29, 95% CI (1.24–1.35); I 2 = 16%]. Stratified analyses indicated higher incidence risk among men (HR = 1.51) and higher mortality risk among women (HR = 1.25). Subgroup analyses further revealed a significant positive association between elevated DII and myocardial infarction (HR = 1.41). In models stratified by diabetes history, unadjusted associations were stronger (HR = 1.40), while adjusted associations were attenuated but remained significant, with a significant interaction ( P = 0.002). Sensitivity and trim-and-fill analyses confirmed the robustness of these associations (all P < 0.001). Conclusion Higher DII scores, reflecting pro-inflammatory dietary patterns, are significantly associated with increased risks of CVD incidence and mortality. These findings underscore the clinical and public health importance of promoting anti-inflammatory dietary strategies to mitigate the global CVD burden. Systematic Review Registration https://www.crd.york.ac.uk/PROSPERO/view/CRD420250654615 , PROSPERO, CRD420250654615.