Coffee consumption is not associated with ovarian cancer incidence.

Coffee contains many substances that could conceivably influence the risk of ovarian cancer. In a meta-analysis of the crude data of seven case-control studies of coffee consumption and ovarian cancer published before 1990, the combined odds ratio was 1.3 [95% confidence interval (95% CI), 1.1-1.5] for coffee users versus nonusers (1). Since then, at least six case-control studies have reported on the association of coffee consumption with ovarian cancer risk. Of these, two studies found a statistically significant increased risk of ovarian cancer associated with coffee consumption (2, 3), one study found a statistically significant inverse association (4), and three studies did not show any significant association (5-7). To date, only two cohort studies, both with a small number of cases, have examined the relation between coffee consumption (assessed at baseline) and ovarian cancer risk. Although coffee consumption was not associated with mortality from ovarian cancer (n = 50 cases) in a cohort of Seventh-day Adventists (8), a Norwegian cohort reported a positive, but statistically nonsignificant, association between coffee consumption and ovarian cancer incidence (n = 93 cases; ref. 9). Given the inconclusive results on coffee consumption and ovarian cancer risk, we sought to prospectively evaluate long-term coffee consumption, using repeated measures of diet, in relation to incidence of invasive epithelial ovarian cancer among 61,057 women in the Swedish Mammography Cohort.