The Relationship between Serum Cortisol and Vitamin C Levels with Obesity

Through hyperactivation of hypothalamic-pituitary-adrenal axis and subsequent elevation of serum cortisol levels, chronic stress might lead to stress-induced hyperphagia and obesity. There are less physical and mental stress signs in people with high level of serum vitamin C. The aim of this study was to assess the relationship between serum vitamin C and cortisol with obesity.Subjects and In this case-control study, 140 healthy women (46 obese and 94 normal weight) 17-44 years old, were recruited using convenient random sampling method. Controls were old-matched. General obesity was defined as BMI≥ 30 Kg/m2 and central obesity as WC≥88 cm. Serum vitamin C and cortisol levels were measured using chemical and ELISA methods, respectively. Since anxiety, depression and eating attitude may be associated with oversecretion of cortisol, we considered them as confounders in our study. The data were analyzed by t-test and logistic regression using SPSS software. There were no significant relationship between serum vitamin C levels with BMI (P=0.70). After adjusting for confounders, women in the highest titres of serum cortisol levels were less likely to have general (OR=0.2, P=0.05) and central obesity (OR=0.2, P=0.02). In this study, there were a significant inverse relationship between serum morning cortisol levels with central and general obesity, while there were no associations between serum vitamin C levels and obesity. To the best of our knowledge, this type of study has never been conducted before in Iranian women; and more studies are required to delineate the nature of these relationships.