The effect of caffeine consumption on serum CK18 protein in non-alcoholic fatty liver disease

The aim of this study is to investigate the association between caffeine intake and serum cytokeratin 18 level (CK18), which is a liver fibrosis indicator in individuals with non-alcoholic fatty liver disease (NAFLD). A total of 20 female and 20 male subjects between the ages of 19-64, who were diagnosed with NAFLD, were included in the study. A questionnaire was administered face-to-face in order to determine individuals' general characteristics, nutrition habits and physical activity status. Twenty-four hour dietary recall and food frequency questionnaire we administered, to determine the nutritional status. Caffeine frequency questionnaire we administered, to determine the caffeine consumption. Anthropometric measurements were taken and blood samples were collected during interviews. The average age of the participants in the study was 39.7 ± 10.66 years in male and 48.1 ± 13.01 years in female subjects (p> 0.05). There was a negative correlation between age and the total amount of daily caffeine consumption (p=0.013). There were positive correlations between the daily caffeine consumption and ALT level (p = 0.003), AST level (p = 0.039), and a negative correlation between the daily caffeine consumption and fasting plasma glucose (p = 0.022). There were no significant correlations between the daily caffeine consumption and anthropometric measurements (p>0.05). There were no significant correlations between serum CK18 level and total caffeine intake (p> 0.05). There was a positive correlation between body fat percentage and serum CK18 level (r = 0.510; p = 0.002). When analyzed according to caffeine sources, there was a negative correlation between the caffeine intake from dark chocolate and serum CK18 level (r =-0.420, p = 0.019). More research is needed to clarify the effect of caffeine consumption on disease-related parameters in individuals with NAFLD.