Method and server in a telecommunication system and a telecommunication system for facilitating weight control

The present publication discloses a method, server, and system for a user's nutrition and exercise monitoring. According to the method, in a telecommunications system (1) information is stored on a server (2) or server group of the telecommunications network (1), and the stored data are provided to users (3) of the telecommunications network. In addition, in the telecommunications network foodstuffs' product and mean- value data, as well as data on forms of exercise are stored on the server (2) or server group, numerically readable codes, such as EAN codes, are combined with the foodstuff and exercise data, the users (3) are allowed to retrieve foodstuff and exercise data from the server (2) or server group, with the aid of product names, or numerically readable, or keyed-in codes, by browsing on the basis of product classifications, or by browsing a favourites list, user-specific physiological information, i.e. basic information, such as the weight, age, or height of the user (3), and variable information, such as the food portions eaten by the user (3) and/or the amount and type of exercise performed by the user, is also stored in the information network (1). According to the invention, the foodstuff, exercise, and user information is combined and models or predictions are created of the nutritional and energy balances of the user (3) utilizing temporal nutrition and exercise entries, on the basis of which the user is guided, by means of the information network, to a target diet and exercise, and information is also stored in the system (2) on the purchases made by the user, with the aid of a point-of- sale system (23), to facilitate the input of variable data on the user.