Coffee consumption has been linked to various beneficial and detrimental health effects, but data on the relation with mortality are sparse.
To assess the association between coffee consumption and mortality from cardiovascular disease (CVD), cancer, and all causes during 18 years of follow-up in men and 24 years of follow-up in women.
Sex-specific Cox proportional hazards models were used to investigate the association between coffee consumption and incidence of death from all causes and specific mortality in a prospective cohort study.
Health Professionals Follow-up Study and Nurses' Health Study.
41,736 men and 86,214 women, without history of CVD or cancer at baseline.
Coffee consumption was first assessed in 1986 for men and in 1980 for women, and then repeatedly every 2-4 years; the follow-up continued through 2004. We documented 6,888 deaths (2,049 due to CVD and 2,491 due to cancer) among men, and 11,095 deaths (2,368 due to CVD and 5,011 due to cancer) among women.
For men, after adjustment for age, smoking, and other CVD and cancer risk factors, the relative risks (RRs) of all cause mortality across categories of coffee consumption (<1cup/mo, 1/mo-4/wk, 5-7/wk, 2-3/d, 4-5/d, and ≥6/d) were: 1.0, 1.07 (95% confidence interval: 0.99-1.16), 1.02 (0.95-1.11), 0.97 (0.89-1.05), 0.93 (0.81-1.07), and 0.80 (0.62-1.04) (p for trend= 0.008); for women, the RRs were: 1.0, 0.98 (0.91-1.05), 0.93 (0.87-0.98), 0.82 (0.77-0.87), 0.74 (0.68-0.81), and 0.83 (0.73-0.95) (p for trend<0.001). This inverse association was mainly due to a moderately reduced risk of CVD mortality, and was independent of caffeine intake. By contrast, coffee consumption was not significantly associated with risk of cancer death after adjustment for potential confounders. Decaffeinated coffee consumption was associated with a small reduction in all cause and CVD mortality.
Some measurement error in the assessment of coffee consumption is inevitable because we estimated the consumption from self-reports.
Regular coffee consumption was not associated with an increased mortality in either men or women. The possibility of a modest benefit of coffee consumption on all cause and CVD mortality needs to be further investigated.