Coffee has been a subject of intense interest for medical researchers for some time, with all sorts of studies aimed at assessing whether coffee ingestion increases or decreases one's risk for any number of conditions or diseases, including but not limited to cancer, high cholesterol, dementia, and death. As I opine in this week's PodMed, seems like those of us who love coffee can finally rejoice and imbibe yet one more cup of Joe, based on a study in the New England Journal of Medicine.
This study used data from the NIH-AARP Diet and Health Study, a very large questionnaire-based sampling of AARP members aged 50 to 71 years. The survey asked questions about 124 dietary items, including consumption of red and white meats, saturated fats, fruits and vegetables, alcohol and coffee, and a host of lifestyle factors such as exercise and smoking. Health status and a number of diseases and conditions impacting health status was also queried. For this analysis data from almost 230,000 men and over 173,000 women were included.
Coffee consumption was pinned down more precisely with 10 frequency categories, ranging from 0 to six or more cups per day. That would be an 8 ounce cup, btw, so those among us who are trying to compare our own habits must take into account the size of our typical cup. Over 95% of respondents provided information on whether they drank caffeinated or decaffeinated coffee (mostly caffeinated), and also what type of coffee they used regularly: 79% drank ground coffee, 19% instant coffee, 1% espresso coffee, and 1% did not specify the type of coffee they consumed.
Interesting but not surprising associations were found along with coffee consumption: more cigarette smoking, more than three alcoholic drinks per day, more red meat consumption. And less exercise, less education, lower consumption of fruits and vegetables.
Death and causes of death were also recorded for this cohort. The numbers were crunched for all-cause and cause-specific mortality in association with coffee consumption and factoring out confounders like cigarette smoking. The study concludes that male coffee drinkers who imbibed 6 or more cups of coffee per day experienced a 10% lower risk of death. Women who consumed six or more cups of coffee per day had a 15% lower risk of death. Now, it must be admitted that this is not a huge benefit, certainly not what is realized by smoking cessation, regular exercise, or careful attention to diet, but not insignificant. And as Rick and I quip, since we're both regular exercisers, don't smoke, aren't overweight and don't eat a bunch of bad stuff, and do drink coffee, we're going to live forever!
Limitations of this study are cited by the authors and we agree: observational studies are rife with possibilities for skewed data, and self-report questionnaires notorious for their unreliability. I did confide to Rick, however, that when a prospective study on coffee drinkers comes to the fore, I'm glad to volunteer as a subject. At the moment it's enough to know that I can keep up my addiction with a clear conscience.
Other topics this week include whether stress testing ought to be done in people who've had procedures to restore blood flow to their hearts in Archives of Internal Medicine, a laxative-free colonoscopy in Annals of Internal Medicine, and how air pollution impacts inflammation in JAMA. Until next week, y'all live well.
Coffee Drinkers Rejoice!,10 Comments