coffee and the risk of lymphoma: a meta-analysis article

background: coffee is implicated in the susceptibility to several cancers. however, the association between coffee and lymphoma remains unclear. this meta-analysis aimed to assess quantitatively the association between coffee and the incidence of lymphoma. methods: a literature search was performed for cohort and case-control studies published using pubmed, cochrane, and embase databases. studies were included if they reported relative ratios (rr) and corresponding 95% confidence intervals (cis) of lymphoma with respect to coffee consumption. pooled relative risk (rr) and its 95% confidence interval (ci) were calculated. all p values are two tailed results: seven studies met the inclusion criteria, which included three cohort and four case-control studies. compared with did not or seldom drink coffee per day, being no significantly association between coffee and risk of lymphoma (pooled rr: 1.05, 95%ci: 0.89-1.23). in the subgroup analysis, no significant association between coffee and lymphoma risk was detected not only in different study types (cohort studies rr: 1.29; 95% ci, 0.92-1.80; case control studies rr: 0.99; 95% ci, 0.82-1.99) but also in different regions (europe rr: 1.21; 95% ci: 0.99-1.47; usa rr: 0.85; 95% ci, 0.62-1.15; asia rr: 1.08, 95% ci: 0.84-1.40) and coffee consumption status (≥4cups/d 1.03, 95% ci: 0.69–1.56; ＜4cups/d rr: 1.06, 95% ci: 0.89- 1.26 ). the funnel plot revealed no evidence for publication bias. conclusion: there was no sufficient evidence to support coffee consumption association with the risk of lymphoma. further well-designed large-scaled cohort studies are needed to provide conclusions that are more definitive.