CONSEDINE, NATHAN S., CAROL MAGAI, FRANCINE CONWAY, AND ALFRED I. NEUGUT. Obesity and awareness of obesity as risk factors for breast cancer in six ethnic groups. Obes Res. 2004;12:1680 -1689. Objective: To document BMI and knowledge regarding obesity as a risk factor for breast cancer among subpopulations of African-, Caribbean-, and European-American women and to consider the variables predicting obesity in these diverse groups. Research Methods and Procedures: A stratified clustersampling plan was used to recruit 1364 older women from Brooklyn, NY, during 2000 -2002. Two groups were born in the United States (African Americans and European Americans), whereas others were from the English-speaking Caribbean, Haiti, the Dominican Republic, and Eastern Europe. Participants provided demographics, height and weight measures, and estimates of the risk obesity posed for breast cancer. Results: Women from all groups were significantly overweight (BMI Ͼ 25 kg/m 2 ), although European Americans were lowest, followed by Dominicans and Haitians; African-American and English-speaking Caribbean women fell into the obese range, even when background variables were controlled. Knowledge of obesity as a breast cancer risk factor was also poor across groups, but Dominicans and Haitians had the lowest scores on knowledge. Importantly, knowledge was not associated with BMI in the overall sample, even when controlling for demographics and ethnicity, although logistic regressions comparing normal weight women with overweight and obese groupings suggested some knowledge of breast cancer risk in the overweight, but not the obese, group. Discussion: The findings remind health professionals of the need to consider more specific ethnic groupings than has hitherto been the case, as well as consider how ethnic and cultural variables may influence perceptions of obesity and its relation to cancer risk.