Coffee consumption can be part of a healthy diet, even for people who consume up to 8 cups a day, according to the results of a study published in JAMA Internal Medicine.
Data collected by Erikka Loftfield, PhD, of the Division of Cancer Epidemiology and Genetics at the National Cancer Institute in Rockville, Maryland, and colleagues from over 500,000 individuals (mean age, 57 years; 54% women, 78% coffee drinkers) in the United Kingdom’s National Health Service indicated that coffee consumption is inversely related to all-cause mortality, “with statistically significant inverse associations observed in participants drinking 1 to 8 or more cups per day.”
Study participants were asked to complete comprehensive questionnaires about their diets and coffee intake from 2006 to 2010. They were also asked about confounding practices such as smoking, alcohol and tea consumption, and about their overall health (body mass index and personal health assessment, among others).
After a decade of follow-up, researchers found that, of the 14,225 participants who died, approximately 58% of deaths were due to cancer, and an additional 20% were due to cardiovascular disease. It was observed that there were inverse associations for each coffee type consumed (ground, instant, decaffeinated) with all-cause and cause-specific mortality. Moreover, associations were generally stronger for ground coffee than for instant or decaffeinated coffee.
Although investigations into the effects of coffee have been conducted before, no prior study has been able to “look at the potential effect modification by caffeine metabolism.” Furthermore, this particular study assessed the potential differences between drinking instant and ground coffee.
“These findings suggest the importance of noncaffeine constitutions in the coffee-mortality association and provide further reassurance that coffee drinking can be part of a healthy diet,” Dr Loftfield and colleagues concluded.
Loftfield E, Corneils MC, Caporaso N, Yu K, Sinha R, Freedman N. Association of coffee drinking with mortality by genetic variation in caffeine metabolism. JAMA Intern Med. 2018;178:1086-1097.