[Causes of undernutrition and how to look for them in general practice].

CAUSES OF UNDERNUTRITION AND HOW TO LOOK FOR THEM IN GENERAL PRACTICE Nutritional imbalance leading to undernutrition is found in 3 situations: in the absence of disease (related to hunger or to socio- economic or psychological problems), related to a disease without inflammation, or to a disease with acute or chronic inflammation. These situations can lead to a reduction in food intake and in digestive absorption, and an increase in energy expenditure and in protein catabolism. In general practice, when faced with unexplained and/or isolated weight loss, whether voluntary or not, it is essential to look for an etiology. Intake can easily be evaluated using a visual or verbal analogical scale, the SEFI (Self-Evaluation of Food Intake). A biological check-up and digestive explorations can also orient the physician towards the cause of this weight loss or undernutrition. There is always a cause for weight loss and the general practitioner is a key player in finding this cause as early as possible.