A method for ordering a meal at a restaurant. Nutritional information of the meal is transferred, and the meal is ordered based on the nutritional information such as on the energy content of the meal and a description of the meal. The meal is assembled based on the nutritional information. A purchase price of the meal, is preferably calculated based on the nutritional information, for instance based solely on the energy (caloric) content of the meal. The nutritional information is preferably logged including a time (and day) of consumption of at least part of the meal. A computerized data base is preferably stored in memory of a computer. The data base includes dietary information of at least one food component, and a scale is operatively attached to the computer. A weight is calculated of an ingredient of the meal based on the nutritional information and the dietary information. Using the scale, the ingredient is weighed and adjusted to approach the calculated weight.