The effects of dietary flavonols on breast cancer risk are unclear. Some flavonol-rich foods appear to have an inverse association, some have none, is what nutritionists can say thus far.
"Laboratory and animal studies suggest that dietary flavonols may reduce breast cancer risk, but there are limited epidemiological studies. We computed flavonol intakes from dietary data collected by validated food frequency questionnaires in 1991 and 1995 from 90,630 women in the Nurses Health Study II. Using multivariate relative risks (RR) and 95% confidence intervals (95% CI), we evaluated the association of flavonol intake with breast cancer risk in women who were premenopausal and aged between 26 and 46 years at baseline in 1991," said C.A. Adebamowo and colleagues, Harvard University.