Objective To systematically evaluate the correlation between coffee and risk of endometrial cancer. Methods Such databases as CBM, CNKI, WanFang data, PubMed, EMbase and The Cochrane Library (Issue 5, 2012) were searched to collect the prospective cohort studies about correlation between coffee and endometrial cancer. The retrieval time was by the end of May 2012, and the references of the included literature were also retrieved. Two evaluators independently screened the literature according to the inclusion and exclusion criteria, extracted the data, and assessed the quality, and then the statistical analysis was conducted by using Stata 12.0 software. Results A total of 10 cohort studies involving 4 484 patients with endometrial cancer were included. The results of meta-analysis showed that, compared with the women who didn’t drink coffee or drank in the lowest dose, the women who drank coffee in the highest dose had a decreased risk of endometrial cancer (RR=0.69, 95%CI 0.62 to 0.78), same as the women who drank coffee frequently (RR=0.83, 95%CI 0.77 to 0.89). The results of dose-response analysis revealed that, when there was an increase of 2 more cups of coffee per day, there was the risk of endometrial cancer decreased by 12%. Conclusion Drinking coffee frequently (more than 2 cups per day) can decrease the risk of endometrial cancer which can be significantly decreased when drinking in a big dose (more than 5 cups per day).
ObjectiveTo systematically evaluate the dose-response relationship between coffee consumption and liver cancer risk. MethodsThe PubMed, Web of Science, Cochrane Library, EMbase, CNKI, VIP, WanFang Data, and CBM databases were searched from inception to December 2022. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. Meta-analysis was then performed by using Stata 17.0 software. ResultsFifteen studies (11 cohort studies and 4 case-control studies) involving 557 259 participants were included. The results of meta-analysis showed that coffee consumption was significantly negatively associated with the risk of liver cancer (RR=0.39, 95%CI 0.27 to 0.57, P<0.01). The dose-response meta-analysis showed a non-linear dose-response relationship between coffee consumption and the risk of liver cancer (P<0.01). Compared with people who did not drink coffee, people who drank 1 cup of coffee a day had a 25% lower risk of liver cancer (RR=0.75, 95%CI 0.67 to 0.83), and people who drank 2 cups of coffee a day had a 38% lower risk of liver cancer (RR=0.62, 95%CI 0.56 to 0.70). The risk of liver cancer decreased by 45% (RR=0.55, 95%CI 0.48 to 0.62) for 3 cups of coffee and by 51% (RR=0.49, 95%CI 0.43 to 0.56) for 4 cups of coffee. ConclusionCurrent evidence suggests that there is a nonlinear dose-response relationship between coffee consumption and the risk of liver cancer. These results indicate that habitual coffee consumption is a protective factor for liver cancer. Due to the limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.
ObjectiveTo investigate whether there is a causal relationship between the intake of milk or coffee and the risk of non-alcoholic fatty liver disease (NAFLD). MethodsUsing a two-sample Mendelian randomization approach, single nucleotide polymorphisms (SNPs) associated with milk or coffee intake were used as instrumental variables, and genome-wide association study data on NAFLD were used as the outcome event. Inverse-variance weighted (IVW) and MR-Egger methods were employed to investigate the causal effect of milk or coffee intake on the risk of NAFLD. ResultsBoth analyses indicated no causal association between milk or coffee intake and the risk of NAFLD (P>0.05). Sensitivity analysis indicated the robustness of the main findings, with no outliers, heterogeneity, horizontal pleiotropy, or significant influence of individual SNPs. ConclusionThis study does not support a causal relationship between the intake of milk or coffee and the risk of NAFLD.