Coffee intake and breast cancer risk in the NIH‐AARP diet and health study cohort

Abstract

There are several biologic mechanisms whereby coffee might reduce breast cancer risk. Caffeine and caffeic acid, major coffee constituents, have been shown to suppress mammary tumor formation in animal models and to inhibit DNA methylation in human breast cancer cells, respectively. Coffee may also reduce risk through decreasing inflammation and influencing estrogen metabolism. However, epidemiologic studies have been inconsistent and few studies have examined the association by estrogen and progesterone receptor (ER/PR) status. We evaluated coffee intake for its effect on incident breast cancer in the NIH-AARP Diet and Health Study cohort, which included 198,404 women aged 50–71 with no history of cancer, who in 1995–1996 completed a questionnaire capturing usual coffee intake over the past year. State cancer registry and mortality index linkage identified 9,915 primary incident breast carcinomas through December 2006; available information on hormone receptor status identified 2,051 ER+/PR+ and 453 ER−/PR− cancers. In multivariate proportional hazards models, coffee intake was not associated with breast cancer risk (p-value for trend=0.38) (relative risk=0.98, 95% confidence interval: 0.91–1.07, for ≥ 4 cups per day as compared to women who never drank coffee), and results did not vary by body mass index or history of benign breast biopsy (p-value for interaction >0.10). We found no evidence of a relationship with either caffeinated or decaffeinated coffee. Null findings persisted for risk of both hormone receptor positive and negative breast cancers. These findings from a large prospective cohort do not support a role of coffee intake in breast carcinogenesis.

Caffeine and Caffeic Acid Inhibit Growth and Modify Estrogen Receptor and Insulin-like Growth Factor I Receptor Levels in Human Breast Cancer

“…Finally, the present study demonstrate that tamoxifen-treated women with ER þ tumors drinking 2 or more cups of coffee per day show a significantly reduced risk of early breast cancer recurrence, compared with women with low daily coffee consumption. Several epidemiologic reports suggest that coffee consumption decreases breast cancer risk (14,25,26), whereas other studies report no association between coffee intake and breast cancer risk (27). However, relatively few studies have examined the association with risk or progression by ER status.…”

Review on Health Benefit and Risk of Coffee Consumption

“…[ [129][130][131][132][133] Coffee drinking cause incontinence Women who drink more than 329 mg of caffeine daily caffeinated coffee exposed for about 70% or more likely to build up incontinence [134][135][136][137] Coffee drinking associated with digestive disorders Upset stomach or indigestion occurs when we drink caffeine [138,139] Coffee drinking can cause headaches Over drinking of coffee cause symptom of a headache due to its caffeine chemical compound.…”

Polyphenols and Breast Cancer Prevention

“…62 Three recent prospective studies not included in the metaanalysis did not show an association of coffee consumption with breast cancer risk. 64 64,73 Although there appears to be a possible association between coffee intake and breast cancer risk, the size of the protective effect seems to be small.…”