Reduce uterine cancer risk - drink coffee
BOSTON, MA--Good news for coffee drinkers: according to a new study, drinking at least four cups of coffee per day is associated with a lower risk for endometrial cancer. Endometrial cancer (cancer of the uterine lining) is the most common form of uterine cancer. According to the National Cancer Institute, there are about 46,000 new cases and 8,000 deaths yearly from the disease.
Researchers at the Harvard School of Public Health in Boston, found that after controlling for a number of factors, compared with women who drank less than one cup of coffee a day, those who drank four or more cups had a 25% lower risk of endometrial cancer. Neither decaffeinated coffee nor tea drinking was associated with a risk reduction; thus, the authors were unable to determine whether caffeine or some other ingredient in coffee causes the effect. Of interest, however, lead author Youjin Je, noted that “a substantial amount of sugar, cream or milk added to coffee can negate the potential benefits.” She also noted that drinking four cups of coffee a day has no negative effects for healthy women. .Ms. Je is a doctoral student in the lab of Edward Giovannucci, MD, ScD, from the Department of Nutrition and Epidemiology at the Harvard School of Public. She and her colleagues published their findings online November 22 in the journal Cancer Epidemiology, Biomarkers & Prevention.
Using prospective data from the Nurses' Health Study, the researchers examined the link between drinking coffee and endometrial cancer risk. The study included data from 67,470 women aged 34 to 59 years in 1980. Cumulative average coffee intake was determined via a questionnaire. During 26 years of follow-up, the researchers documented 672 cases of endometrial cancer. Drinking fewer than four cups of coffee per day was not associated with a change in endometrial cancer risk compared with drinking one or less cups per day. The researchers accounted for numerous factors in their analysis, including BMI, age at menopause, age at menarche, parity (number of pregnancies) and age at last birth, oral contraceptive use, postmenopausal hormone use, smoking, and alcohol consumption.
Drinking four or more cups of coffee per day was associated with a 25% relative risk reduction compared with consuming less than one cup daily. Drinking between two and three cups of coffee per day was linked with a 7% reduced risk; however, the difference was not statistically significant. In terms of absolute risk reduction, women who drank four or more cups of coffee reduced their risk for endometrial cancer from 56 cases per 100,000 women to 35 cases per 100,000 women. The researchers found a similar association when they restricted their analysis to caffeinated coffee consumption. In that case, there was a 30% relative risk reduction in endometrial cancer risk associated with consumption of four or more cups compared with less than one cup a day. For decaffeinated coffee consumption, drinking two or more cups per day was linked with a 22% relative reduction in risk for endometrial cancer vs. drinking less than one cup per month; however, the difference was not statistically significant.
In subgroup analyses, there was a stronger inverse association with high coffee intake among obese women. The authors wrote: "Because obese women tend to have insulin resistance, oxidative stress, and relatively low levels of [sex hormone binding globulin], the potential abilities of coffee to improve those conditions may have contributed to a decreased risk of endometrial cancer among obese women.” Dr. Giovanucci noted, “Coffee has already been shown to be protective against diabetes due to its effect on insulin; so we hypothesized that we'd see a reduction in some cancers as well." According to Dr. Giovannucci, laboratory testing has found that coffee has many more antioxidants than most vegetables and fruits.