Omega-3 Polyunsaturated Fatty Acids Can Reduce C-Reactive Protein in Patients with Cancer: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Omega-3 polyunsaturated fatty adds (PUFAs) possess anti-inflammatory properties. There is a lack of consensus regarding the effects of omega-3 PUFAs on C-reactive protein (CRP), a marker of systemic inflammation, in cancer patients. Herein, a meta-analysis of randomized controlled trials was conducted to evaluate the effects of omega-3 PUFAs on CRP levels in patients with cancer. PubMed and EMBASE were searched until May 2020 to identify randomized controlled trials that examined the effects of omega-3 PUFA administration on CRP levels in cancer patients. Standardized mean differences (SMDs) with their 95% confidence intervals (Cs) were calculated to determine the differences in omega-3 PUFA administration and control conditions. Seventeen eligible studies involving 916 cancer patients were included in this meta-analysis. Significant heterogeneity was present among individual studies (P-heterogeneity = 0.000; p = 74.5%). The overall SMDs of CRP levels between omega-3 PUFA administration and control conditions were 0.628 (95% CI: 0.342-0.914) and 0.456 (95% CI: 0.322-0.590) by the random-effect and fixed-effect models, respectively. Sources of heterogeneity were not found through subgroup and meta-regression analyses. Existing publication bias contributed slightly to the effect size. Omega-3 PUFAs can reduce systemic inflammation, as indicated by CRP levels in cancer patients. The use of omega-3 PUFAs is recommended for cancer patients due to their anti-inflammatory properties.