Objectives: There has been a rise in the number of overweight women across the globe and sub-Saharan Africa has not been spared. Our objective was to describe the performance of household food security as a factor in determining overweight and underweight among Kenyan women of child-bearing age. Design: A cross sectional survey using a structured questionnaire was carried out among 656 households with women of child-bearing age from both rural and urban settings in the Rift Valley, Kenya. Results: Of all households involved, 70.1% were categorized as severely food insecure, 21.9% were moderately food insecure, and 3.7% were mildly food insecure, whereas 4.3% were food secure. Urban women had higher mean BMI (M = 24.53, SD = 4.36), compared to rural women (M = 22.52, SD = 3.71; P <0.000). Households with more children had decreased dietary diversity (r = −0.154; P <0.01). Logistical regression indicated that more food-secure households (OR = 0.97; 95% CI 9.4, 1.0), urban residence (OR = 1.82; 95% CI 1.1, 3.0), older age (OR = 1.10; 95% CI 1.1, 1.5), and high standard of living (OR = 1.79; 95% CI 1.2, 1.5) were strong predictors of overweight while being underweight was predicted by younger age (OR = 0.91; 95% CI, 0.83, 1.0). Conclusions: A food-secure household does not predict underweight but predicts overweight among women.