MedicalResearch.com Interview with:
Ming Ding, MD, DSc
Departments of Nutrition and Epidemiology
Harvard T.H. Chan School of Public Health
Medical Research: What is the background for this study?
Response: Coffee is one of the most commonly consumed beverages worldwide. Previous studies showed coffee consumption was associated with a lower risk of type 2 diabetes, cardiovascular disease, liver disease, and Parkinson’s disease. However, the association between coffee consumption and risk of mortality remains uncertain. Some studies showed an inverse association between moderate coffee consumption and risk of mortality, and an inverse or null association between heavy coffee consumption and risk of mortality. However, some studies found heavy coffee consumption to be associated with higher risk of mortality.
Medical Research: What are the main findings?
Response: With 208,501 participants and 31,956 deaths in three large cohort studies, our results showed a non-linear association of coffee consumption with total mortality in the whole population. When restricting to never smokers, coffee consumption was associated with lower risk of total mortality, and mortality due to CVD, neurological diseases, and suicide. No association of coffee consumption with cancer mortality was found. The present study provides strong evidence that long-term coffee consumption is not associated with increased risk of mortality.
Medical Research: What should clinicians and patients take away from your report?
Response: Coffee drinking was associated with a lower risk of total mortality and mortality due to cardiovascular disease, neurological diseases, and suicide. Similar associations of caffeinated and decaffeinated coffee consumption with risk of total and cause-specific mortality were found. Therefore, coffee consumption can be incorporated into a healthy lifestyle. However, as we do not know whether coffee drinking has acute effect on blood pressure, it is safer to consume moderate amount of coffee (3 to 5 cups per day or up to 400 mg/d caffeine).
Medical Research: What recommendations do you have for future research as a result of this study?
Response: First, the biological mechanism of the inverse association between coffee drinking and risk of mortality is not known. It has been shown the chlorogenic acid, lignans, quinides, trigonelline, and magnesium in coffee might reduce insulin resistance and systematic inflammation.
However, it still needs further investigation how those nutrients functions.
Second, using a perspective cohort design, our study examined the association of long-term coffee drinking with risk of mortality. However, coffee might have an acute effect on blood pressure due to caffeine. This research question is worth further exploration.
Ming Ding, MD, DSc (2015). Moderate Coffee Habit Associated With Lower Risk of Mortality