The present invention provides a method for evaluating nutritional components in a course. The method comprising the steps of: providing users with information of courses including: menus, characteristics of each course, description of courses, applying predefined interaction computerized procedure for each type of user's profile,wherein said procedure enables the user to navigate through course information and define the modes of interacting with a user or a sensor associated with the user which relate to metabolic effect for each type of user by commenting, providing additional information or correcting said information, tracking and recording user's actions and behavior through the interaction procedure or the navigation, classifying users according profile type based on input parameters defined by the user, classifying users to groups based on their action and behaviors, analyzing user's actions and behaviors for evaluating metabolic effects and users preferences in relation to course information, determining user's degree of credibility based on user's actions, behaviors and profile and calculating nutritional values of courses based on evaluated metabolic reactions, determined credibility and users classification in relation to course information.