Association between green tea/coffee consumption and biliary tract cancer: A population‐based cohort study in Japan

Abstract

Green tea and coffee consumption may decrease the risk of some types of cancers. However, their effects on biliary tract cancer (BTC) have been poorly understood. In this population‐based prospective cohort study in Japan, we investigated the association of green tea (total green tea, Sencha, and Bancha/Genmaicha) and coffee consumption with the risk for BTC and its subtypes, gallbladder cancer, and extrahepatic bile duct cancer. The hazard ratios and 95% confidence intervals were calculated using the Cox proportional hazard model. A total of 89 555 people aged 45–74 years were enrolled between 1995 and 1999 and followed up for 1 138 623 person‐years until 2010, during which 284 cases of BTC were identified. Consumption of >720 mL/day green tea was significantly associated with decreased risk compared with consumption of ≤120 mL/day (hazard ratio = 0.67 [95% confidence interval, 0.46–0.97]), and a non‐significant trend of decreased risk associated with increased consumption was observed (P‐trend = 0.095). In the analysis according to the location of the primary tumor, consuming >120 mL green tea tended to be associated with decreased risk of gallbladder cancer and extrahepatic bile duct cancer. When Sencha and Bancha/Genmaicha were analyzed separately, we observed a non‐significant trend of decreased risk of BTC associated with Sencha but no association with Bancha/Genmaicha. For coffee, there was no clear association with biliary tract, gallbladder, or extrahepatic bile duct cancer. Our findings suggest that high green tea consumption may lower the risk of BTC, and the effect may be attributable to Sencha consumption.

Peer pressure and its influence on consumers in Taiwan

“…The more peer pressure there is, the more customers are likely to follow their friends to buy certain products. This is in agreement with previous studies such as Gulati (2017), Makiuchi (2016), Nirupma (2015), Akar et al (2015), etc. For this reason, it is likely that the impact of peer pressure on consumers" decision is universal and entrepreneurs can take advantage of that phenomenon.…”

Coffee and green tea consumption and subsequent risk of acute myeloid leukemia and myelodysplastic syndromes in Japan

“…Further, subjects were selected from the general population, and the response rate to the questionnaire (>80%) was acceptable for this study setting while the loss to follow‐up (0.8%) was negligible. The limitations of analyses derived from the JPHC study have been described in previous articles . Here, we mention only important limitations specifically inherent to this study.…”

“…The limitations of analyses derived from the JPHC study have been described in previous articles. 11,35,36 Here, we mention only important limitations specifically inherent to this study. First, we could not evaluate the risk of AML and MDS by subtype because most cases were categorized as having an unspecified subtype.…”

The relationship between vegetable/fruit consumption and gallbladder/bile duct cancer: A population‐based cohort study in Japan

“…The consumption of individual food groups and nutrients was adjusted for total energy using residual method and categorized into quartiles based on the consumption in all participants with the lowest consumption category as the reference. This multivariate analysis model was adjusted for the following potential confounders which were biologically a priori and/or were considered associated with general cancer risk or the risk of biliary cancers: age (continuous); study area (10 PHC areas); sex (men/women); body mass index (<23, 23–25, 25–27, ≥27 kg/m 2 ); history of cholelithiasis (no/yes); history of diabetes mellitus (no/yes); history of chronic hepatitis or cirrhosis (no/yes); history of smoking (no, past or current, unknown); alcohol drinking frequency (never or almost never, one to three times/month, one to two times/week, three to four times/week, ≥5 times/week, unknown); physical activity by metabolic equivalents/day (quartiles, unknown); green tea consumption (≤120, 120–360, 360–720, or >720 mL/day, unknown); energy‐adjusted consumption of fish (quartiles) and red meat (quartiles).…”

“…All statistical analyses were performed using Stata version 13 (Stata Corporation, College Station, TX). We referred to the previous studies about biliary cancers for the study method …”