Nutritional status and nutritional therapy in inflammatory bowel diseases

Table 1 Pathophysiology of malnutrition

Main mechanism	Effect
Decreased food intake	Anorexia
	Abdominal pain, nausea, vomiting
	Restricted diets
	Drugs
Nutrients malabsorption	Reduced absorptive surface due to inflammation, resection, bypass and fistulae
Increased intestinal loss	Exudative enteropathy (protein loss)
	Occult/overt blood loss (iron deficiency)
	Diarrhea (increased loss of Zn2+, K+, Mg2+)
	Steatorrhea (fat and fat soluble vitamin malabsorption, and divalent cations’ loss: Zn2+, Mg2+, Ca2+, Cu2+)
Hypermetabolic state	Alterations of resting energy expenditure
Drugs' interaction	Anorexia, nausea, test alteration, proteolysis, interaction with nutrients absorption/utilization