A/Prof David van der Poorten
Dr Roslyn Vongsuvanh
  Professor Golo Ahlenstiel
Dr Way Siow & Dr Rishi Sud
Email: admin@sydneynwgastro.com.au
Appointments & Enquiries:  (02) 8711 0160

The Small Intestine

The small intestine (small bowel) starts after the stomach and comprises the 4 parts of the duodenum, the jejunum and the ileum. It measures close to 6m in length. After food leaves the stomach, pancreatic enzymes and bile are added in the 2nd part of the duodenum to assist with breaking down carbohydrates and fats. Nutrient absorption occurs within the small bowel, with each region having specific functions. For example the jejunum absorbs proteins, iron, calcium, vitamin D and folate, while the ileum absorbs B12, carbohydrates etc. The small intestine ends at the terminal ileum where undigested matter passes into the colon.


Common diseases of the small intestine include:

  • Coeliac disease
  • Small bowel bacterial overgrowth
  • Crohn’s disease
  • Irritable bowel syndrome ** (all parts of the intestine can be involved)
  • Infections (both acute and chronic)