Data from 6,969 subjects 18y or older participating in the Second Wave of the Mexican Family Life Survey, 2005(SWMFLS-2005) a large cohort representative of the Mexican population were collected. The objective was to evaluate the association between obesity and risk factors associated with metabolic syndrome (MS). Methods: Prevalences of obesity (BMI > 30 kg/mt2), high systolic and diastolic blood pressure (¡Ý 140 and ¡Ý 90 mmHg), high serum glucose (¡Ý 126g/dL) and hypercholesterolemia (¡Ý 200 mg/dL) were obtained. Hypertension was defined as high systolic and or diastolic pressure. Results: Prevalences were: obesity (22.8%), high glucose (9.5%), hypertension (4.5%) and hypercholesterolemia (18.3%). The prevalence in obese compared with non obese were: high glucose 12.8% vs. 6.1%. Hypercholesterolemia 20.5% vs. 15.2%, Hypertension 4.5% vs. 2.2%. With few exceptions, those with obesity were more likely to have hypertension OR= 4.32 (3.13, 5.95); diabetes OR=2.07 (1.56, 2.74) and hypercholesterolemia OR=1.40(1.1, 1.8), compared with those with normal BMI, adjusting for age and sex. Conclusions: The results show that obesity is risk factors for chronic diseases in Mexican adults.