Due to an imbalance between the bodies needs and the daily intake of nutrients.
Inadequate intake, malabsorption, abnormal loss (eg diarrhoea) undernutrition
Overeating, insufficient exercise overnutrition
Risk factors for undernutrition:
Grossly underweight; loss of >10 bodyweight during 3 months; high alcohol intake; no oral intake for >10 days; malabsorption syndrome, diabetes, renal dialysis, increased metabolic need (eg infections, burns, trauma, fever).
Based on medical history, diet history, physical examination and laboratory tests (complete blood count, plasma proteins, plasma lipids, minerals)