Overweight and micronutrient deficiencies have manifested in the same individuals. This study investigated the association among iron deficiency (ID), anemia, and weight status among nonpregnant Colombian females aged 13-49 y (n = 3267). Data from the 2005 National Survey of the Nutrition Situation were used. The prevalence of ID (plasma ferritin <12.0 mu g/L; individuals with CRP >0.012 g/L excluded) and anemia (altitude-adjusted hemoglobin <120 g/L) was estimated separately. The likelihood of having ID or anemia was tested as a function of overweight (BMI-age Z-score 1-1.9 SD for 13-17 y, BMI 25.0-29.9 kg/m(2) for 18-49 y) and obesity (>= 2 SD for 13-17 y, >= 30 kg/m(2) for 18-49 y) using multivariate logistic regressions accounting for survey design. Additionally, demographic predictors of combined oveweight/obesity with ID or anemia were identified. The prevalence of overweight and obesity was 29.2 and 13.1%, respectively, whereas that of ID and anemia was 16.1 and 32.5%, respectively. Contrary to previous reports, overweight and obese women had a lower likelihood of anemia [OR (95% Cl) = 0.8 (0.7, 0.9) and 0.8 (0.6, 1.0), respectively] than normal-weight women. Overweight/obesity combined with ID or anemia was present among 6.3 and 12.8% of women, respectively. Although overweight and obesity were associated with a lower likelihood of anemia, a sizeable group of women was identified as experiencing both over- and undernutrition. Because of the potential for exacerbated health problems in the presence of over- and undernutrition, these conditions should continue to be monitored. J. Nutr. 143: 175-181, 2013.