New Studies Suggest that Coffee may Reduce the Risk of Endometrial Cancer
Coffee is one of the most commonly consumed beverages in the world. According to authors Dicum and Luttinger of The coffee book: anatomy of an industry from the crop to the last drop, approximately 2.25 billion cups of coffee are consumed every day worldwide. Although coffee has had a convoluted history when it comes to health benefits, recent research shows great promise.
A recent study was published a few weeks ago in Cancer Epidemiology, Biomarkers, and Prevention journal which stated that women who drank four or more cups of coffee daily had a reduced risk of endometrial cancer.
Endometrial cancer is a cancer that stems from the endometrium, which is the inner lining of the uterus. Based on statistics from the National Cancer Institute in 2014, it is the second most frequent female cancer after breast cancer. It commonly arises in postmenopausal women, and has a high correlation to obesity. According to the World Health Organization (WHO), approximately 40% of endometrial cancer cases are related to obesity.
The risk factors for endometrial cancer are most commonly hormonal related. Patients who present with high estrogen levels are much more likely to contract endometrial cancer. According to Hoffman et al., high levels of obesity translates to more adipose tissue. This adipose tissue converts androstenedione to estrone, an estrogen. In addition, some other factors such as: polycystic ovary syndrome (PCOS), long periods of estrogen replacement therapy, and late menopause can all lead to endometrial cancer.
How? PCOS causes irregular to no ovulation. Ovulation results in the endometrium being sloughed off if not fertilized by an egg. If the body cannot ovulate (or there is obstruction to ovulation), this leads to a thickened endometrium, increasing the risk. Estrogen replacement therapy is most commonly administered to women who have severe discomfort such as hot flashes when going through menopause. However, according to Soliman et al., if the therapy is long or in high doses, this will lead to high estrogen levels, which could cause endometrial cancer. When someone has late menopause, it extends the window of time for fertility. As a result, the endometrium will be exposed to more estrogen over a longer period of time, making these patients more susceptible to endometrial cancer as well.
The 2015 research study, headed by Dr. Melissa Merritt from Imperial College London, looks at what they call, “a nutrient wide association study”. The scientists used a series of questionnaires from a population of approximately 1,300 women to determine if there is a correlation between certain foods/beverages and the incidence of endometrial cancer. They did suggest an, “inverse relationship between coffee intake and the risk of endometrial cancer.” There are two important things to note. First, this study is associative not causative. Therefore, we still don't fully know if coffee can reduce the cause for endometrial cancer. Second, this is a relatively small sample size. As a result, we need to turn our attention to a second study, which was published in 2011.
A study by Youjin et al. published in the same academic journal, Cancer Epidemiology, Biomarkers, and Prevention, looks at the association between coffee and endometrial cancer over a 26-year span. There was a net amount (not counting those who passed away during the 26 year interval) of 67,040 test subjects, a significantly larger number than the new 2015 study. The conclusion of the study reads, “Prospective data suggests that four or more cups of coffee per day are associated with a lower risk of endometrial cancer.” In addition, this study looks at regular and decaffeinated coffee as well as tea. The results showed the best inverse correlation with regular coffee as opposed to decaf and/or tea. According to the paper, three suggested mechanisms to decrease the risk of endometrial cancer include: a high caffeine intake decreases insulin concentration, frees estrogen thus reducing estrogen levels, and increases antioxidants due to phenols. As stated earlier, when estrogen levels are reduced, this decreases the chance of contracting endometrial cancer.
There is one major caveat regarding the aforementioned study. It specifically states that the results found resulted from black coffee consumption. The addition of cream and sugar is not exactly known. Therefore, the idea that four or more cups of coffee daily potentially reducing the risk of endometrial cancer only applies to black coffee. Moreover, although caffeine has many benefits, drinking four or more cups of coffee daily is quite a lot. Thus, it is important to consider your personal tolerance to caffeine and ensure that the benefits outweigh the risks. Both studies do conclude that more studies need to be conducted. In general, medical/scientific research has been finding more and more benefits for coffee recently, but it is important to consider the longevity and sample size of the studies. As always, please consult your doctor/health care professional before starting any dietary program, including increasing coffee consumption. In conclusion, these studies show great promise for endometrial cancer prevention moving forward. Because of the prevalence of endometrial cancer, this can be of great benefit to women worldwide.
About SC Ali
S.C. Ali is an author/editor. He has a degree in Chemistry, and is interested in the study and practice of medicine. His blog can be found here: http://thebronzelifestyle.com/