大豆食品摄入与乳腺癌发病关系的Meta分析

目的探讨大豆食品摄入与乳腺癌发病的关系。方法检索1991年到2011年4月公开发表的关于大豆食品摄入与乳腺癌关系的流行病学研究进行Meta分析,结果报告合并比值比(OR)及95%可信区间(95%CI)。结果 28个研究纳入Meta分析,其中有23个病例对照研究,5个队列研究。总体分析,大豆食品摄入对乳腺癌具有保护作用(合并OR=0.86,95%CI 0.78～0.94),但按设计类型分层后,只有病例对照研究的结果显示大豆食品对乳腺癌具有保护作用(合并OR=0.86,95%CI 0.77～0.95)。在不同国家和地区人群中开展的研究结果显示,在亚洲地区人群中,合并OR=0.76(95%CI 0.67～0.87),而欧美地区人群的研究合并OR=1.01(95%CI 0.93～1.09)。对在亚洲地区人群中开展的病例对照研究和队列研究分别进行合并分析,结果显示大豆食品摄入对乳腺癌均具有保护作用,合并OR分别为0.76(95%CI 0.65～0.89)和0.81(95%CI 0.70～0.92)。但在欧美地区人群中开展的两类研究均未发现大豆食品摄入对乳腺癌有保护作用。根据绝经前后的亚组分析结果显示,仅在绝经后女性中大豆食品摄入对乳腺癌起保护作用。结论根据亚洲地区人群中开展的研究,尤其是病例对照研究结果的合并分析,提示大豆食品摄入对亚洲地区女性乳腺癌具有保护作用。     

Green tea and gastric cancer risk: meta-analysis of epidemiologic studies

OBJECTIVE: To evaluate the association between green tea consumption and the risk of gastric cancer. METHODS: Electronic search of the Cochrane Library, MEDLINE, EMBASE and Chinese Bio-medicine Database, which have articles published between (1966 and 2006), was conducted to select studies for this meta-analysis. RESULTS: This meta-analysis included 14 epidemiologic studies, with a total number of 6123 gastric cancer cases and 134006 controls. The combined results based on all studies showed that green tea consumption was not associated with the risk of gastric cancer [odds ratio (OR)=0.98, 95% confidence interval (CI)=0.77-1.24]. The summary OR from all population-based case-control studies showed a minor inverse association between green tea consumption and risk of gastric cancer (OR=0.68, 95% CI=0.49-0.92), while no associations were noted from hospital-based case-control studies (OR=1.12, 95% CI=0.70-1.77) and cohort studies (OR=1.56, 95% CI=0.93-2.60). No associations were noted both in males (OR=1.10, 95% CI=0.76-1.60) and females (OR=0.99, 95% CI=0.64-1.51). The summary OR from seven studies suggest that the highest consumption level of green tea was more than 5 cups per day and no associations were noted (OR=0.99, 95% CI=0.78-1.27). CONCLUSIONS: The results of this meta-analysis indicated that there is no clear epidemiological evidence to support the suggestion that green tea plays a role in the prevention of gastric cancer.     

Coffee consumption and the risk of incident gastric cancer—A meta-analysis of prospective cohort studies

As several epidemiological studies on the association of coffee consumption with gastric cancer risk have produced inconsistent results, this meta-analysis was designed to synthesize current evidence of this potential relationship. We searched PubMed, EMBASE, and the Cochrane Library up to September 2014 to retrieve relevant articles. Prospective cohort studies were included if the relative risks (RRs) or hazard ratios and 95% confidence intervals (CIs) for gastric cancer according to coffee consumption were reported. Fixed- or random-effects models were used based on heterogeneity. The search yielded 13 eligible cohort studies of 3484 incident gastric cancer patients from among 1,324,559 participants. A significantly increased risk was found between gastric cardia cancer and coffee consumption (RR = 1.50, 95% CI: 1.09–2.07). Compared with Europeans (RR = 1.12, 95% CI: 0.86–1.46) and Asians (RR = 0.96, 95% CI: 0.72–1.27), Americans (RR = 1.36, 95% CI: 1.06–1.74) demonstrated a significantly positive association. However, the significant differences of the pooled results vanished after adjusting for smoking or body mass index. Our meta-analysis results suggest that a high level of coffee consumption is a risk factor for gastric cancer. However, these results should not be overinterpreted because residual confounding effects of other factors could exist.     

酒精摄入与女性乳腺癌发病风险的Meta分析

目的 探讨酒精摄入与女性乳腺癌发病风险的关联性。方法 通过Stata 12.0软件对国内外发表的有关酒精摄入与女性乳腺癌发病风险的队列研究和病例对照研究进行Meta分析。结果 共纳入16项病例对照研究和15项队列研究,包括50 519例患者和973 216例对照者。病例对照研究Meta分析提示,酒精暴露可明显增加女性个体发生乳腺癌的风险,合并OR值为1.18,95％置信区间为1.05～1.32;以绝经状态为亚组的Meta分析提示,酒精暴露可增加绝经后女性个体发生乳腺癌的风险,合并OR值为1.26,95％置信区间为1.08～1.46。队列研究Meta分析提示,有酒精暴露者女性乳腺癌的发生率是非饮酒者的1.1倍,合并RR值为1.10,95％置信区间为1.06～1.15;以绝经状态为亚组的Meta分析提示,有酒精暴露的绝经后女性乳腺癌的发生率是非饮酒者的1.1倍,合并RR值为1.14,95％置信区间为1.10～1.19。结论 酒精摄入可显著提高女性尤其绝经后乳腺癌的发病风险。     

Milk consumption and bladder cancer risk: a meta-analysis of published epidemiological studies

Studies investigating the association of milk consumption with bladder cancer risk have reported inconsistent findings. We conducted a meta-analysis of published cohort and case-control studies to pool the risk estimates of the association between milk intake and bladder cancer. We quantified associations with bladder cancer using meta-analysis of odds ratio (OR) associated with the highest vs. the lowest category of milk intake using fixed- or random-effect models depending on the heterogeneity of effects among studies. Nineteen cohort and case-control studies were eligible for inclusion. High milk intake was significantly associated with decreased risk of bladder cancer (OR, 0.84; 95% CI, 0.71-0.97) when comparing the highest with the lowest category of milk intake. The inverse association was stronger in Asia (OR, 0.60; 95% CI, 0.40-0.81) than North America (OR, 0.89; 95% CI, 0.76-1.03), and no association was observed in Europe (OR, 1.05; 95% CI, 0.85-1.26). This relationship also varied significantly by specific dairy products. Our results suggest that milk may be related to the reduction of bladder cancer risk. Further studies need to clarify the biological mechanisms.     

ILIB启动子区多态性与癌症风险的meta分析

IL1B（Interleukin 1 beta）是一种对抗感染的前炎症因子,在肿瘤的发生发展中起着重要的作用。IL1B基因启动子区-31C／T多态性位点通过影响IL1B的转录参与癌症的发生。针对已有的研究存在结论不一致的现状,为了阐明两者之间的关系,我们对47篇发表的病例对照研究进行meta分析,其中包括11125病例和14415例对照。比值比（Odds Ratio,OR）和95％可信区间（CI）用来评估多态性位点与癌症风险的关联程度。在所有的对比中没有发现此多态性位点与所有癌症相关联。通过分层分析发现,携带C等位基因的个体比不带C等位基因的个体患肝癌的风险低（CCVS TT：OR=0．87,95％CI：0．77—0．98,Phetermgrenty=0．103;TC vs TT：OR=0．77,95％CI：0．62-0．95,Phetermgrenty=0．734;TC＋CC vs TT：OR=0．74,95％CI：0．61～0．91,Phetermgrenty=0．472）。同样,C／C基因型个体相比T,T基因型个体患胃癌风险低（OR=0．87,95％CI：0．77-0．98,Rhetermgrenty=0．103）。运用隐性模型,患胃癌的风险显著下降（OR=0．88,95％CI：0．80～0．97,Phetermgrenty=0．158）,在欧洲人群（OR=0．84,95％CI：0．73-0．97,Phetermgrenty=0．070）和感染-配埘研究（OR=0．75,95％CI：0．60～0．94,Phetermgrenty=0．220）中都发现有显著下降的风险;在乳腺癌中有显著增加的风险（OR=1．34,95％CI：1．18～1．61,Phetermgrenty=0．116）。虽然一些适度偏倚不能消除,此meta分析显示IL1B-3IC基因型是癌症发生的保护因素,特别是在感染人群中。     

Meta-analysis of multiple myeloma and benzene exposure.

Epidemiologic studies have suggested that benzene exposure may be a risk factor of multiple myeloma (MM). We performed meta-analyses of case-control studies to assess the association between occupational exposure to benzene and the risk of MM. We divided the occupational sources of benzene exposure into 4 categories, benzene and/or organic solvents, petroleum, petroleum products, and engine exhaust, for conducting the meta-analysis. As a result, a significant positive association was indicated between exposure to engine exhaust and MM (summary odds ratio or summary OR=1.34, 95% confidence interval or 95%CI=1.14-1.57). However, no significant associations were obtained for benzene and/or organic solvents (summary OR=0.74, 95%CI=0.60-0.90), petroleum (summary OR=1.11, 95%CI=0.96-1.28) and petroleum products (summary OR=1.08, 95%CI=0.89-1.33) with risk of MM. These results suggested that benzene exposure itself was not likely to be a risk factor of MM. It is thought that several harmful chemical agents in engine exhaust, other than benzene, could be etiologically related to the risk of MM. Further case-control studies on MM are needed to obtain more information about detailed occupational exposure to toxic substances.     

Coffee Drinking and the Risk of Endometrial Cancer: An Updated Meta-Analysis of Observational Studies

Background: Several compounds contained in coffee have been found to suppress carcinogenesis in experimental studies. We conducted a dose–response meta-analysis to assess the impact of coffee consumption on the risk of endometrial cancer. Materials and methods: We searched MEDLINE and EMBASE databases for studies published up to August 2016. Using random effects models, we estimated summary relative risks (RR) for cohort studies and odds ratios (OR) for case-control studies with 95% confidence intervals (CI). Dose–response analyses were conducted by using generalized least square trend estimation. Results: We identified 12 cohort studies and 8 case-control studies eligible for inclusion, contributing with 11,663 and 2,746 endometrial cancer cases, respectively. The summary RR for highest compared with lowest coffee intake was 0.74 (95% CI: 0.68–0.81; p_{heterogeneity} = 0.09, I² = 32%). The corresponding summary RR among cohort studies was 0.78 (95% CI: 0.71–0.85; p_{heterogeneity} = 0.14, I² = 31.9%) and 0.63 (95% CI: 0.53–0.76; p_{heterogeneity} = 0.57, I² = 0%) for case-control studies. One-cup increment per day was associated with 3% risk reduction (95% CI: 2–4%) in cohort studies and 12% (95% CI: 5–18%) in case-control studies. After pooling the results from 5 cohort studies, the association remained significant only in women with body mass index over 30 (RR = 0.71, 95% CI: 0.61–0.81). Conclusion: The results from our meta-analysis strengthen the evidence of a protective effect of coffee consumption on the risk of EC and further suggest that increased coffee intake might be particularly beneficial for women with obesity.     

咖啡摄入量与心血管死亡率关系的剂量-反应Meta分析

目的 探讨咖啡每日摄入量与心血管死亡率的关系。方法 计算机检索PubMed、EMbase、The Cochrane、CBM、WanFang Data和CNKI 数据库,搜集有关咖啡摄入量与心血管疾病的相关研究,检索时限均从建库至2020年4月。由两名研究者独立筛选文献、提取文献并评价纳入研究的偏倚风险后,采用Stata 14.0进行剂量反应meta分析,并对纳入的文献进行方法学质量评价。结果 共纳入26篇队列研究,包括2 046 690例受试者。剂量-反应meta分析结果显示,咖啡摄入量每天每增加1杯心血管死亡率下降约3%（RR = 0.97,95%CI:0.96～0.98）,差异具有统计学意义,且存在一种非线性剂量反应关系（P for non - linearity:＜0.01）。与不喝咖啡的人群相比,每天喝1～8杯咖啡的人群相对死亡率分别为（RR = 0.90,95%CI:0.87～0.92）、（RR = 0.84,95%CI:0.81～0.87)、（RR = 0.82,95%CI:0.79～0.84）、（RR = 0.81,95%CI:0.78～0.84）、（RR = 0.81,95%CI:0.78～0.84）、（RR = 0.81,95%CI:0.78～0.84）、（RR = 0.82,95%CI:0.79～0.85）、（RR = 0.83,95%CI:0.80～0.87）。与不喝咖啡人群相比,meta分析结果显示喝咖啡人群的相对死亡率平均为（RR = 0.83,95%CI:0.81～0.85）,可以降低17%的死亡率,差异具有统计学意义。结论 饮用咖啡可以降低心血管死亡率,每日饮用2～4杯最佳。     

Meta-analysis of studies on individual consumption of chlorinated drinking water and bladder cancer

STUDY OBJECTIVE: To evaluate whether consumption of chlorinated drinking water is associated with bladder cancer. DESIGN: A bibliographic search was conducted and the authors selected studies evaluating individual consumption of chlorinated drinking water and bladder cancer. The authors extracted from each study risk estimates for intermediate and long term (>40 years) consumption of chlorinated water, stratified by sex when possible, and performed meta-analysis for the two exposure levels. A meta-analysis was also performed of the dose-response regression slopes. SETTING: Populations in Europe and North America. PARTICIPANTS: Those included in six case-control studies (6084 incident bladder cancer cases, 10,816 controls) and two cohort studies (124 incident bladder cancer cases) fulfilling the inclusion criteria. MAIN RESULTS: Ever consumption of chlorinated drinking water was associated with an increased risk of bladder cancer in men (combined OR=1.4, 95%CI 1.1 to 1.9) and women (combined OR=1.2, 95%CI 0.7 to 1.8). The combined OR for mid-term exposure in both genders was 1.1 (95% CI 1.0 to 1.2) and for long term exposure was 1.4 (95%CI 1.2 to 1.7). The combined estimate of the slope for a linear increase in risk was 1.13 (95% CI 1.08 to 1.20) for 20 years and 1.27 (95% CI 1.15 to 1.43) for 40 years of exposure in both sexes. CONCLUSIONS: This meta-analysis of the best available epidemiological evidence indicates that long term consumption of chlorinated drinking water is associated with bladder cancer, particularly in men. The observed relative risk is only moderately high, but the population attributable risk could be important as the vast majority of the population of industrialised countries is potentially exposed to chlorination byproducts for long time periods.     

Meta-Analysis of Black Tea Consumption and Breast Cancer Risk: Update 2013

Black tea is a commonly consumed beverage in the world, comprising approximately 80% of all tea consumed. We sought to examine the association between black tea consumption and risk of breast cancer, using all available epidemiologic evidence to date. PubMed, EMBASE, ISI Web of Science, Chinese National Knowledge Infrastructure Database, and China Biological Medicine Database were used to search for citations using the MeSH terms as “breast neoplasm” AND “black tea.” Then we performed a meta-analysis of studies of breast cancer risk published between 1985 and 2013 by using RevMan 5.0 software. The results showed that no association between black tea consumption and breast cancer risk in overall [odds ratio (OR) = 0.97; 95% confidence interval (CI) = 0.89–1.05]. We further performed a stratified analysis according to region (United States/Europe). Black tea consumption did not decrease breast cancer risk in the United States (OR = 0.91; 95% CI = 0.78–1.07) and in Europe (OR = 0.99; 95% CI = 0.93–1.06). In addition, the summary OR from all cohort studies (OR = 1.04, 95% CI = 0.91–1.18) or all case-control studies (OR = 0.95, 95% CI = 0.88–1.02) showed black tea intake has no effects on breast cancer risk. However, the association between black tea consumption and breast cancer incidence remains unclear based on the current evidence. Further well-designed large studies are needed to confirm our result.     

Milk Consumption and Bladder Cancer Risk: A Meta-Analysis of Published Epidemiological Studies

Studies investigating the association of milk consumption with bladder cancer risk have reported inconsistent findings. We conducted a meta-analysis of published cohort and case-control studies to pool the risk estimates of the association between milk intake and bladder cancer. We quantified associations with bladder cancer using meta-analysis of odds ratio (OR) associated with the highest vs. the lowest category of milk intake using fixed- or random-effect models depending on the heterogeneity of effects among studies. Nineteen cohort and case-control studies were eligible for inclusion. High milk intake was significantly associated with decreased risk of bladder cancer (OR, 0.84; 95% CI, 0.71–0.97) when comparing the highest with the lowest category of milk intake. The inverse association was stronger in Asia (OR, 0.60; 95% CI, 0.40–0.81) than North America (OR, 0.89; 95% CI, 0.76–1.03), and no association was observed in Europe (OR, 1.05; 95% CI, 0.85–1.26). This relationship also varied significantly by specific dairy products. Our results suggest that milk may be related to the reduction of bladder cancer risk. Further studies need to clarify the biological mechanisms.     

Occupational risks for laryngeal cancer: a case-control study

The most solidly established risk factors for laryngeal cancer are tobacco and alcohol. As for occupational factors, the only established carcinogen is exposure to strong inorganic acid mists. However, asbestos, pesticides, paints, gasoline, diesel engine emissions, dusts, and other factors have been reported in the literature as occupational agents that increase the risk of laryngeal cancer. A hospital-based case-control study was conducted to investigate occupational risk factors for laryngeal cancer. Detailed data on smoking, alcohol consumption, and occupational history were collected for 122 laryngeal cancers and 187 controls matched by frequency (according to sex and age). Laryngeal cancer was associated with exposure to respirable free crystalline silica (OR = 1.83; 95%CI: 1.00-3.36), soot (from coal, coke, fuel oil, or wood) (odds ratio - OR = 1.78; 95% confidence interval - 95%CI: 1.03-3.03), fumes (OR = 2.55; 95%CI: 1.14-5.67), and live animals (OR = 1.80; 95%CI: 1.02-3.19).     

Dairy Consumption and Gastric Cancer Risk: A Meta-Analysis of Epidemiological Studies

Studies investigating the association of dairy consumption with gastric cancer risk have reported inconsistent findings. We conducted this systematic review and meta-analysis to review and summarize the epidemiologic evidence on the relation of total dairy and milk consumption with risk of gastric cancer. We summarized the available literature on this topic using meta-analysis of relative risks (RR) associated with total dairy and milk intake. The total of 17 case-control and 6 cohort studies (3256 cases) were eligible for inclusion. When comparing the highest with the lowest category of total dairy intake, the results of cohort studies indicated that increased consumption of total dairy food was associated with a reduced risk of gastric cancer (RR = 0.76; 95% CI: 0.64–0.91), whereas case-control studies provided no association. In subgroup analysis, significantly inverse associations between total diary food consumption and gastric cancer risk were observed in Europe subgroup (RR = 0.73; 95% CI: 0.54–0.99), U.S. subgroup (RR = 0.78; 95% CI: 0.63–0.98) but not in Asia subgroup. However, milk consumption was not associated with gastric cancer risk no matter in main or subgroup analysis. The results of cohort studies, but not case-control studies, suggested that total dairy might be related to the reduction of gastric cancer risk. Milk consumption was not associated with gastric cancer risk.     

Citrus fruits intake and prostate cancer risk: a quantitative systematic review

OBJECTIVES: The purpose of this systematic review was to investigate the association between dietary intake of citrus fruits and prostate cancer risk. METHODS: Authors searched electronic databases and the reference lists of publications of diet and prostate cancer studies until August 2007. All of the epidemiological studies that obtained individual data on dietary intake of citrus fruits and presented risk estimates of the association between intake of citrus fruits and risk of prostate cancer were identified and included. Using general variance-based methods, study-specific odds ratios (OR)/ relative risk (RR) and associated confidence interval (CI)/ standard error (SE) for highest versus lowest intake of citrus fruits level were extracted from each paper. RESULTS: Eleven articles including six case-control studies, one nested case-control study and four cohort studies, proved eligible. Overall summary OR using random effect model did not show an association in risk of prostate cancer with intake of citrus fruits (summary OR=1.03, 95% CI=0.89-1.19) with large heterogeneity across studies that we were unable to explain (I(2)=67.88%). The summary ORs in case-control studies and cohort studies were 1.10 (95% CI=0.97-1.22) and 1.05 (95% CI=0.96-1.14), respectively. CONCLUSIONS: Pooled results from observational studies did not show an association between intake of citrus fruits and the risk of prostate cancer, although results vary substantially across studies.     

The Effect of Daily Fluid Management and Beverages Consumption on the Risk of Bladder Cancer: A Meta-analysis of Observational Study

Epidemiological studies have evaluated the risk of bladder cancer (BCa) in relation to total fluid intake, as well as specific type of beverages consumption, with controversial results. The aim of this study was to further explore the potential relationship by conducting a meta-analysis. Fifty-four articles involving more than 43,000 BCa patients were included in this meta-analysis. A positive, though not statistically significant, association was found between total fluid intake and risk of BCa comparing the highest with lowest intake (SRRE: 1.16, 95%CI: 1.00–1.36). By conducting dose-response meta-analysis, we found that each 500?ml/day increase in total fluid intake was associated with 3.3% increased risk of BCa (RR: 1.03, 95%CI: 1.00–1.07). Pronounced increase in risk of BCa was detected when total fluid intake was more than 3000?ml/day. Meta-analyses of specific type of beverages showed increasing intake of coffee (RR: 1.03, 95%CI: 1.02–1.05) were risk factors for BCa. On the contrary, increasing intake of milk appeared to be a potential protective factor for BCa (RR: 0.90, 95%CI: 0.83–0.98). The risk of BCa was not significantly related to intake of water (RR: 1.01, 95%CI: 0.98–1.03), alcohol (RR: 1.01, 95%CI: 0.97–1.05), tea (RR: 1.01, 95%CI: 0.97–1.05) and soft drinks (RR: 1.04, 95%CI: 0.96–1.11).     

中国女性乳腺癌危险因素的Meta分析

目的:评价中国女性乳腺癌部分危险因素的作用,探索乳腺癌的病因。方法:运用Meta分析方法对我国1996～2006年间公开发表的有关乳腺癌危险因素病例对照研究的12篇文献资料进行定量综合分析。结果:各因素合并OR值分别为:初潮年龄(年)OR=1.54(95%CI:1.3437～1.7654);哺乳OR=0.68(95%CI:0.4779～0.9782);口服避孕药OR=1.33(95%CI:1.0627～1.6589);良性乳腺疾病史OR=2.62(95%CI:2.0275～3.3804);吸烟OR=1.86(95%CI:1.5394～2.2415);饮酒OR=0.81(95%CI:0.6196～1.0686);饮茶OR=0.86(95%CI:0.7646～0.9728)。结论:初潮年龄、口服避孕药、良性乳腺疾病史及吸烟是乳腺癌发生的危险因素,哺乳及饮茶则是乳腺癌的保护因素。     

骨质疏松与认知障碍关系的Meta分析

目的 系统评价骨质疏松与认知障碍的关系,为认知障碍患者的预防提供循证支持。方法 计算机全面检索Embase,Web of Science,PubMed,Cochrane Library,知网,中国生物医学文献数据库,万方,维普等数据库中关于认知障碍与骨质疏松关系的队列研究及病例-对照研究,时限均自建库至2021年4月23日。所得数据采用RevMan 5.3结合Stata 15.1软件进行Meta分析。结果 最终纳入7篇文献,共77417个患者。纳入文献均为中高等质量水平。Meta分析结果显示:与对照组相比,骨质疏松组认知障碍的发病率更高（OR=1.97,95% CI:1.37～2.82,P<0.001）。同时,亚组分析结果显示,不同性别［男性（OR=1.68,95% CI:1.22～2.32,P=0.001）、女性（OR=1.76,95% CI:1.28～2.42,P<0.001）］、年龄［老年（OR=1.77,95% CI:1.26～2.50,P=0.001）、中年（OR=2.38,95% CI:1.43～3.97,P=0.001）］、测量部位［腰椎（OR=2.18,95% CI:1.49～3.20,P<0.001）、股骨颈（OR=2.41,95% CI:1.23～4.73,P=0.010）］、认知障碍严重程度［痴呆（OR=2.22,95% CI:1.63～3.03,P<0.001）］、国家［亚洲（OR=2.31,95% CI:1.61～3.30,P<0.001）］下,认知障碍与骨质疏松症呈正关联。结论 骨质疏松与认知障碍的风险增加有关。     

Consumption of Tea and Risk for Pancreatic Cancer: A Meta-Analysis of Published Epidemiological Studies

Epidemiologic studies on the relationship between tea consumption and pancreatic cancer are inconsistent. Therefore, we conducted a systematic search of databases and performed a meta-analysis to analyze the association between tea consumption and risk of pancreatic cancer. We searched Medline, EMBASE, ISI Web of Science, and the Cochrane library for studies of tea consumption and pancreatic cancer published up to December 2012. Subgroup analysis was conducted by study type, study region, sex, type of tea, without or with adjustment for smoking, and body mass index. We performed a meta-analysis of 8 case-control studies and 6 cohort studies. For pancreatic cancer, the summary odds ratio (OR) for highest vs. lowest was 0.95 (95% confidence interval (CI), 0.84–1.08). The summary OR for moderate vs. lowest was 1.07 (95% CI, 0.86–1.35). The summary OR for ever vs. lowest was 1.00 (95% CI, 0.86–1.16). The results of this meta-analysis suggested tea consumption is not related to pancreatic cancer risk, even at high doses. Because of the small number of studies, further prospective studies are needed.