Use of food supplements and determinants of usage in a sample Italian adult population.

OBJECTIVE The aims were to collect data on consumption of different food supplements in a sample of the adult Italian population and to characterize users by demographic, physical and health-related characteristics, lifestyle and behaviour. DESIGN Cross-sectional survey. SETTING The study was conducted in 2008 in ten towns of Italy (two towns from each of the five macro-areas: Northwest, Northeast, Centre, South and Islands). SUBJECTS Adults (n 10 000) aged ≥18 years were randomly selected and asked to fill in a self-administered questionnaire regarding their use of food supplements and the above variables. The effect of these variables on food supplement use was evaluated by univariate and multivariate logistic regression. RESULTS Of the 1723 individuals who returned the questionnaire, 49% were users of food supplements. A large proportion (54%) of users used more than one category of food supplement: vitamin and/or mineral supplements were the most used (61%), followed by supplements with botanicals and botanical extracts (28%). The results obtained by logistic regression showed that gender, town size, education level, sports practice, regular use of wholemeal cereal-based foods and presence of a low stress level were determinants for the use of food supplements in the examined population. However, these determinants were not shared by all categories of supplements. CONCLUSIONS The results of this preliminary study highlight that associations between demographic, dietary and lifestyle factors and use of different categories of food supplements differ according to products, and cannot be accounted for simply by dichotomizing individuals as users or non-users.