Malabsorption affects both macro and micronutrient absorption2.
Carbohydrate malabsorption may result from mucosal damage, short bowel syndrome or congenital intestinal enzyme or transport deficiencies4. Damage caused to the intestinal mucosa can lead to brush border enzyme deficiencies such as sucrase-isomaltase, lactase and glucoamylase – present on the villous tips in the jejunum and most of the ileum.
Protein malabsorption alone is rare. Protein digestion survives in most conditions except in cystic fibrosis and intestinal damage can cause protein-losing enteropathy in the gut1,4.
Fat malabsorption alone is uncommon. It is usually associated with protein and carbohydrate malabsorption. Steatorrhoea may occur: the excessive passage of fat in the faeces. Fat-soluble vitamin A, D, E and K deficiency often co-exists1-4.
Table 2: Effects of micronutrient malabsorption2.