OBJECTIVE: To estimate the direct medical costs associated with obesity in France. DESIGN: Analysis of the French 1991-1992 National Household Survey database comprising a representative sample of 14,670 individuals aged 18 y and over. A subgroup of subjects with a body mass index (BMI) 30 kg/m2 was compared with a control group of normal-weight individuals (BMI 18.5-25 kg/m2) matched on age, gender and education level. MEASUREMENTS: Self-reported weight and height used to calculate individual body mass index and health expenditures in a 3 month period, and morbidity as declared by respondents to the national household survey and verified on medical records. RESULTS: The direct cost attributable to obesity (BMI30 kg/m2) was estimated to be in the range 4.2-8.7 billion French Francs (FF) in 1992 value, that is between 0.7 and 1.5% of total health expenditures. CONCLUSION: These results were of the same order of magnitude as similar estimates obtained by a top-down approach for the same year and setting. International Journal of Obesity (2000) 24, 151-155 | 
