Coffee drinking has been suggested to protect against liver injury, but it is uncertain
whether this is of clinical significance. We examined the relationship of coffee and
tea consumption with the incidence of hospitalization or death from chronic liver
disease (CLD).
Participants in the population-based, first National Health and Nutrition Examination
Survey, 1971-1975, were asked about coffee and tea consumption, which was categorized
as <1 cup (mean, 0.2 cups), 1 to 2 cups, and >2 cups per day (mean, 4.0 cups). A second
analysis included persons who, in 1982-1984, were asked more detailed questions on
coffee and tea drinking. Participants were followed through 1992-1993 for a hospital
or death certificate diagnosis of CLD or cirrhosis (ICD-9-CM 571). Hazard rate ratios
for CLD according to coffee and tea intake were calculated using Cox proportional
hazards analysis.
Among 9849 persons followed for a median of 19.0 years (range, 0.02-22.1), the cumulative
incidence of CLD was 1.4%. In multivariate analysis, participants who drank >2 cups
per day had less than half the rate of CLD as those who drank <1 cup per day (hazard
ratio, 0.43, 95% confidence interval: 0.24-0.78). Protection by coffee and tea was
limited to persons at higher risk for liver diseases from heavier alcohol intake,
overweight, diabetes, or high iron saturation. Among 9650 participants who provided
detailed drink information in 1982-1984, intake of regular ground coffee and of caffeine
was associated with lower incidence of CLD.
Coffee and tea drinking decreases the risk of clinically significant CLD.