As I sit down to write this, sipping my second cup of the day, I am delighting in the fact that I am enjoying something that may actually be good for me. Coffee.
More and more data is emerging about the benefits of these little aromatic beans. In fact, a simple Pubmed (database of medical literature) search of “coffee and cancer,” turns up 1400+ publications with 150+ related to breast cancer. Although the data remains a bit uncertain, there does seem to be an association of lower breast cancer risk with higher amounts of coffee intake, particularly in postmenopausal women and in BRCA1 mutation carriers. The most comprehensive study looking into the relationship of breast cancer risk and coffee intake was a meta-analysis published in 2013, a combined look of 37 different published articles on the topic. While there was no clear relationship between coffee and/or caffeine intake with breast cancer incidence in the population as a whole, there was definitely a suggestion of a benefit in the two groups mentioned above.
What is the mechanism, you ask? Well, a recent article published in Clinical Cancer Research suggests that caffeine may work to sensitize hormone receptor positive tumor cells to tamoxifen and may even reduce breast cancer cell growth, at least in a test tube. In addition, coffee is known to be a rich source of anti-oxidants, another cancer-fighting mechanism. More investigation is clearly needed to tease out which groups of individuals might benefit more or less from our favorite morning pick-me-up, but at the very least, I think it’s safe to say to go ahead and have another cup.
Along with this potential anti-breast cancer benefit, there are several other cancers with good data demonstrating the anti-tumor effect of coffee:
It should be noted that these studies show an association between caffeine and cancer reduction but do not necessarily imply causation. In fact, some associations determined from observational studies have subsequently been found to be incorrect when tested in a clinical trial. Nevertheless, it is quite intriguing that these associations are found in multiple types of cancer.
Another interesting thing about these studies is that across the board, there does not seem to be any effect with decaf coffee, implicating the caffeine as the operative agent. In addition, it is the higher amounts of caffeine intake that seem to make a difference. So, does that mean you should go to your local coffee shop and chain yourself to a chair? No. Keep in mind, there are safe amounts of coffee to consume. This link is useful as a general guide to appropriate caffeine intake. Everyone has different sensitivities to caffeine, which need to be factored in as well.
The bottom line is, coffee is proving to be a lifestyle intervention that may offer some benefit to reduce the incidence of certain types of cancer. It will be interesting to watch the data as it becomes more mature and more specific to which groups are gaining the most benefit. I will likely be found reading that literature with a cup of joe in hand.
1. Loftfield E, Freedman ND, Graubard BI, et al. Coffee drinking and cutaneous melanoma risk in the NIH-AARP diet and health study. J Natl Cancer Inst. 2015 Jan 20. Epub ahead of print
2. Holick CN, Smith SG, Giovannucci E, Michaud DS. Coffee, Tea, Caffeine Intake, and Risk of Adult Glioma in Three Prospective Cohort Studies. Cancer Epidemiol Biomarkers Prev. 2010;19:39-47.
3. Merritt MA, Tzoulaki I, Tworoger SS, et al. 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. Cancer Epidemiol Biomarkers Prev. 2015;24:466-71.
4. Geybels MS, Neuhouser ML, Wright JL, et al. Coffee and tea consumption in relation to prostate cancer prognosis. Cancer Causes Control. 2013;24:1947-54. NOTE: This study investigated the potential benefit of coffee in reducing the risk of recurrence or progression of prostate cancer.
5. Setiawan VW, Wilkens LR, Hernandez BY, et al. Coffee intake reduces hepatocellular carcinoma risk: The Multiethnic Cohort. American Association for Cancer Research Annual Meeting 2014; April 5–9, 2014; San Diego. Abstr LB-281.
6. Galeone C, Tavani A, Pelucchi C, et al. Coffee and tea intake and risk of head and neck cancer: pooled analysis in the international head and neck cancer epidemiology consortium. Cancer Epidemiol Biomarkers Prev. 2010;19:1723-36.