We hypothesized that exposure to phthalates was related with obesity and insulin resistance, and we aimed to evaluate the levels of the primary and secondary metabolites of DEHP in urine in obese and normal-weight subjects both before and during puberty, and to investigate their relationships with auxological parameters and indexes of insulin sensitivity using both traditional statistical analysis (i.e.Mann-Whitney test, Kruskall-Wallis ANOVA, correlation tests) and Auto-CM analysis. The gene discussed is INS; the disease is Obesity.