Benefit-risk of coffee consumption and all-cause mortality: A systematic review and disability adjusted life year analysis.

Background: Recommendations and guidance from scientific bodies do not provide clear messages about potential health risks or benefits of coffee consumption. Numerous studies have demonstrated inverse (beneficial) effects of coffee consumption for many adverse outcomes such as cancer and cardiovascular disease; fewer studies demonstrate risks. However, the risk-benefit relationship has not yet been fully assessed using quantitative metrics preferred by policy makers (disability-adjusted life years [DALYs]).

Objective: Conduct a quantitative analysis of the risk-benefit for coffee consumption and all-cause mortality using the Benefit-Risk Analysis for Foods (BRAFO) framework and the DALY as a quantitative metric.

Method: A systematic search and appraisal of meta-analyses investigating coffee consumption and all-cause mortality was conducted. Using the BRAFO framework, evidence was assessed in context of potential risks or benefits associated with the reference scenario - coffee consumption (assessed by varying the consumption level in three analyses) in adults aged 15+ versus the alternative scenario of no coffee consumption. DALYs were used to quantify risks and benefits based on risk ratios from meta-analyses with populations from the United States.

Results: Meta-analyses consistently report an inverse (beneficial) relationship between coffee consumption and all-cause mortality; subsequently, even while varying consumption amounts and prevalence of coffee consumption, DALYs calculated consistently demonstrated findings in the direction of prevention of healthy years of life lost with variable magnitude. More than 3.5 million DALYs, or ∼3.35% of estimated years of healthy life lost could be prevented by consuming one cup of coffee per day, up to 4.7% of estimated years of healthy life lost could be prevented at current consumption rates ranging from 1 to 8 cups/day, and even more benefit could be seen (prevention of an estimated 6% of years of healthy life lost) if consumers all drank 3 cups of coffee per day.

Impact: Policy that directs consumers to avoid drinking coffee may be a detriment to the overall health of the population given the substantial potential benefits of coffee consumption on all-cause mortality for adults.