BackgroundEstrogen receptor-negative (ER(-)) breast cancer has few known or modifiable risk factors. Because ER(-) tumors account for only 15% to 20% of breast cancers, large pooled analyses are necessary to evaluate precisely the suspected inverse association between fruit and vegetable intake and risk of ER(-) breast cancer.MethodsAmong 993 466 women followed for 11 to 20 years in 20 cohort studies, we documented 19 869 estrogen receptor positive (ER(+)) and 4821 ER(-) breast cancers. We calculated study-specific multivariable relative risks (RRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression analyses and then combined them using a random-effects model. All statistical tests were two-sided.ResultsTotal fruit and vegetable intake was statistically significantly inversely associated with risk of ER(-) breast cancer but not with risk of breast cancer overall or of ER(+) tumors. The inverse association for ER(-) tumors was observed primarily for vegetable consumption. The pooled relative risks comparing the highest vs lowest quintile of total vegetable consumption were 0.82 (95% CI = 0.74 to 0.90) for ER(-) breast cancer and 1.04 (95% CI = 0.97 to 1.11) for ER(+) breast cancer (P (common-effects) by ER status < .001).="" total="" fruit="" consumption="" was="" non-statistically="" significantly="" associated="" with="" risk="" of="" er(-)="" breast="" cancer="" (pooled="" multivariable="" rr="" comparing="" the="" highest="" vs="" lowest="" quintile="0.94," 95%="" ci="0.85" to="" 1.04).conclusionswe="" observed="" no="" association="" between="" total="" fruit="" and="" vegetable="" intake="" and="" risk="" of="" overall="" breast="" cancer.="" however,="" vegetable="" consumption="" was="" inversely="" associated="" with="" risk="" of="" er(-)="" breast="" cancer="" in="" our="" large="" pooled="" analyses.="">