Obesity problems are no longer limited to the USA as, in recent years, obesity rates in the EU countries have increased dramatically, leading to serious consequences in terms of direct health care costs and productivity losses, and indicating the existence of a negative externality connected with obesity. Several studies have investigated the private and social costs of obesity, and possible interventions to reduce this pathology. Moreover, a number of economic studies deals with the analysis of variables affecting overweight. Following this last approach and focusing on Italy, the purpose of this paper is to analyse the socio-economic variables affecting obesity, by means of a survey conducted on a sample of 955 consumers resident in Lombardy. The sample was stratified by the variables of gender, age, and residence of the interviewees and was representative of the Lombardy population. We used an ordinal regression model as the dependent variable is expressed in terms of BMI ordinal categories. The independent variables in the model are 14, and are connected to socio-demographic characteristics, nutritional claims, food product attributes, consumer healthy life attitude. The results show that the condition of the seriously overweight, and obese people, increases with age, and this is especially so in people over 65 where the obesity rate is quite high. Also gender is correlated with the pathology, those affected being more likely to be men. Furthermore, there is an inverse relation between obesity and education, obesity decreasing with increasing level of education. Therefore, the analysis underlined that disadvantaged social categories are more susceptible to obesity and overweight. Interestingly, it was found that an inverse relation exists between obesity and quality and marketing attributes of food products.