Basics in clinical nutrition: Simple and stress starvation

Humans adapt well to short- or a longer-term starvation, using their reserve stores of carbohydrates, fat and protein. Reduction of energy expenditure and conservation of body protein are further reaction to starvation. Energy stores are replenished during feeding period. Long-term partial or total cessation of energy intake leads to marasmic wasting. With the addition of the stress response, catabolism and wasting are accelerated and the normal adaptive responses to simple starvation are over-ridden. Weight loss in either situation results in impaired mental and physical function, as well as poorer clinical outcome. Previously malnourished subjects have less reserves with which to face an acute illness. They are unable to release sufficient amounts of endogenous nitrogen in response to trauma and infection with subsequent higher mortality, more complications and prolonged recovery. If surgery is planned in these patients nutritional support improves physiological functions and lessen surgical risk. © 2008 European Society for Clinical Nutrition and Metabolism.