Nutritional value of diets disclosed in non-scientific magazines - doi: 10.5020/18061230.2010.p349

Abstract

Objective: To assess the nutritional value of weight-loss diets disclosed in non-scientific magazines. Methods: A quantitative cross-sectional study carried out in two phases (first investigation in 2007; second investigation in 2009), in which 120 weight-loss diets were randomly selected from 24 magazines divided into three groups based on cost. The menus were evaluated with regard to calories, macronutrients and fiber, using the Diet Pro 2 program. The SPSS program (version 15.0) was used for statistical analysis, with the results expressed as mean, standard deviation and confidence intervals. Two-way analysis of variance (ANOVA) with Tukey’s paired post hoc comparison was used for the quantitative study of the nutrients in each group of magazines and each phase of the study. The Student’s t-test was used for the comparisons of mean values obtained with the diets and established recommendations. The level of significance was set at 5.0%. Results: The energy supply was higher in 2007. Over time, mean protein content in the diets diminished, lipid content remained similar and glucose content increased. Based on the recommended values, the diets were characterized as hypoglycemic, high-protein and normolipidemic. The content of micronutrients was lower than recommended amounts in both years assessed. The fiber content increased in the second year in relation to the first, but did not reach the recommended level. Conclusion: Diets showed inadequacies of macro and micronutrients in the two studied years, with an imbalance between their components.