A system and method for monitoring and regulating blood glucose values in blood circulation. The system includes an input device for receiving at least one blood glucose value measured in the blood circulation, at least one insulin value previously supplied to the blood circulation by at least one insulin supply device, and/or at least one nutrition value of at least one artificial nutrition agent previously supplied to the blood circulation by at least one nutrition supply device. The system also includes a computer for calculating a new insulin value and optionally a new nutrition value according to the influence thereof on blood glucose values and according to the previously measured blood glucose value, and an output device for outputting the new insulin values and optionally nutrition values.