A Prospective Cohort Study of Coffee Consumption and Risk of Endometrial Cancer over a 26-Year Follow-Up

Abstract

Background Coffee has been reported to lower levels of estrogen and insulin, two hormones implicated in endometrial carcinogenesis, but prospective data on the relation between coffee consumption and risk of endometrial cancer are limited. Methods We prospectively assessed coffee consumption in relation to endometrial cancer risk in the Nurses’ Health Study (NHS) with 67,470 female participants aged 34–59 in 1980. Cumulative average coffee intake was calculated with all available questionnaires to assess long-term effects. Cox regression models were used to calculate incidence rate ratios (RR), controlling for other risk factors. Results Fewer than 4 cups of coffee per day were not associated with endometrial cancer risk. However, women who consumed 4 or more cups of coffee had 25% lower risk of endometrial cancer than those who consumed less than 1 cup per day (multivariable RR=0.75; 95% CI =0.57–0.97; Ptrend = 0.02). We found the similar association with caffeinated coffee consumption (RR for ≥ 4 vs. <1 cup/day = 0.70; 95% CI = 0.51–0.95). For decaffeinated coffee consumption, a suggestive inverse association was found among women who consumed 2 or more cups per day vs. <1 cup/month. Tea consumption was not associated with endometrial cancer risk. Conclusions These prospective data suggest that 4 or more cups of coffee per day are associated with a lower risk of endometrial cancer. Impact Drinking of coffee, given its widespread consumption, might be an additional strategy to reduce endometrial cancer risk. However, addition of substantial sugar and cream to coffee could offset any potential benefits.

Intake of coffee, caffeine and other methylxanthines and risk of Type I vs Type II endometrial cancer

“…Consistent with our results, four recent studies found an inverse association of coffee with EC, particularly among women with BMI ⩾30 kg m −2 (Friberg et al , 2009; Giri et al , 2011; Gunter et al , 2011; Je et al , 2011). For the first time, we extend this association specifically to Type I EC and to coffee but not other common sources of methylxanthines, which were not addressed by these prior studies.…”

Investigation of Dietary Factors and Endometrial Cancer Risk Using a Nutrient-wide Association Study Approach in the EPIC and Nurses' Health Study (NHS) and NHSII

“…The inverse association between coffee intake and EC risk is consistent with two recent meta-analyses (3, 13) and an earlier NHS report (14). Obesity is a strong risk factor for EC (2) and may act by increasing exposure to estrogen (15) and/or hyperinsulinemia (16).…”

“…Increasing consumption of caffeine and caffeine-containing coffee was associated with higher levels of adiponectin in the NHS which may benefit insulin sensitivity (18), and also with elevated levels of sex hormone-binding globulin (SHBG) that may decrease bioavailable estrogen based on a report focusing on postmenopausal women in the Rancho Bernardo community-based study (19). However, epidemiologic evidence suggests that non-caffeine components of coffee may be important for the risk reduction based on observations in the WCRF meta-analysis (3) that the decreased risk for EC is similar in magnitude for decaffeinated coffee, and because drinking tea which also contains caffeine does not appear to be related to EC risk in the current study and in the earlier NHS report (14) and WCRF meta-analysis (3). …”

A Prospective Investigation of Coffee Drinking and Bladder Cancer Incidence in the United States

“…It contains over 1000 chemical compounds, many of which, including caffeine, diterpenes, and phenolic acids, are known to be bioactive. 1 Strong inverse associations of coffee drinking with liver cancer 2 and endometrial cancer 3, 4 have been consistently observed. However, evidence of an association with other cancers, including breast, 5 prostate, 6 and lung 7 is less consistent.…”