Coffee and tea consumption and risk of pre- and postmenopausal breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study
Authors: Bhoo-Pathy Nirmala , Peeters Petra HM , Uiterwaal Cuno SPM , Bueno-de-Mesquita H Bas , Bulgiba Awang M , Bech Bodil Hammer , Overvad Kim , Tjønneland Anne , Olsen Anja , Clavel-Chapelon Françoise , Fagherazzi Guy , Perquier Florence , Teucher Birgit , Kaaks Rudolf , Schütze Madlen , Boeing Heiner , Lagiou Pagona , Orfanos Philippos , Trichopoulou Antonia , Agnoli Claudia , Mattiello Amalia , Palli Domenico , Tumino Rosario , Sacerdote Carlotta , van Duijnhoven Franzel JB , Braaten Tonje , Lund Eiliv , Skeie Guri , Redondo María-Luisa , Buckland Genevieve , Pérez Maria José Sánchez , Chirlaque Maria-Dolores , Ardanaz Eva , Amiano Pilar , Wirfält Elisabet , Wallström Peter , Johansson Ingegerd , Nilsson Lena Maria , Khaw Kay-Tee , Wareham Nick , Allen Naomi E , Key Timothy J , Rinaldi Sabina , Romieu Isabelle , Gallo Valentina , Riboli Elio , van Gils Carla H 
Published: January 2015

Abstract
Introduction
Specific coffee subtypes and tea may impact risk of pre- and post-menopausal breast cancer differently. We investigated the association between coffee (total, caffeinated, decaffeinated) and tea intake and risk of breast cancer.

Methods
A total of 335,060 women participating in the European Prospective Investigation into Nutrition and Cancer (EPIC) Study, completed a dietary questionnaire from 1992 to 2000, and were followed-up until 2010 for incidence of breast cancer. Hazard ratios (HR) of breast cancer by country-specific, as well as cohort-wide categories of beverage intake were estimated.

Results
During an average follow-up of 11 years, 1064 premenopausal, and 9134 postmenopausal breast cancers were diagnosed. Caffeinated coffee intake was associated with lower risk of postmenopausal breast cancer: adjusted HR = 0.90, 95% confidence interval (CI): 0.82 to 0.98, for high versus low consumption; Ptrend = 0.029. While there was no significant effect modification by hormone receptor status (P = 0.711), linear trend for lower risk of breast cancer with increasing caffeinated coffee intake was clearest for estrogen and progesterone receptor negative (ER-PR-), postmenopausal breast cancer (P = 0.008). For every 100 ml increase in caffeinated coffee intake, the risk of ER-PR- breast cancer was lower by 4% (adjusted HR: 0.96, 95% CI: 0.93 to 1.00). Non-consumers of decaffeinated coffee had lower risk of postmenopausal breast cancer (adjusted HR = 0.89; 95% CI: 0.80 to 0.99) compared to low consumers, without evidence of dose–response relationship (Ptrend = 0.128). Exclusive decaffeinated coffee consumption was not related to postmenopausal breast cancer risk, compared to any decaffeinated-low caffeinated intake (adjusted HR = 0.97; 95% CI: 0.82 to 1.14), or to no intake of any coffee (HR: 0.96; 95%: 0.82 to 1.14). Caffeinated and decaffeinated coffee were not associated with premenopausal breast cancer. Tea intake was neither associated with pre- nor post-menopausal breast cancer.

Conclusions
Higher caffeinated coffee intake may be associated with lower risk of postmenopausal breast cancer. Decaffeinated coffee intake does not seem to be associated with breast cancer.