Digestive Tract Overview

The digestive tract is a continuous pathway from mouth to anus that processes food and absorbs nutrients.

An ostomy bypasses part of the digestive tract, bringing waste out through a stoma into an external pouch.

Stomach

Absorbs water, ethyl alcohol, copper, iodine, fluoride.

No major impact from an ostomy. Digestion begins as usual.

Duodenum (First part of the Small Intestine)

Absorbs calcium, phosphorus, magnesium, iron, vitamins A, D, E, K, thiamin, riboflavin, niacin, biotin, folate.

If bypassed in certain surgeries, absorption of calcium, iron, and fat-soluble vitamins (A, D, E, K) may decrease.

Jejunum (Middle part of the Small Intestine)

Absorbs fats, sugars (monosaccharides), amino acids, small peptides, vitamins (B1, B2, B3, B5, B6, B9, B12, C, A, D, E, K), minerals (calcium, phosphorus, iron, zinc, chromium, manganese, molybdenum).

If a large part is bypassed, there may be malabsorption of fats, proteins, carbohydrates, and vitamins.

Ileum (Last part of the Small Intestine)

Food passes from the small intestine to the colon for final water absorption before stool formation. Absorbs vitamin C, folate, vitamin B12, vitamin D, vitamin K, magnesium, bile salts, and acids.

Ileostomy impact: 🚨 Vitamin B12, carbohydrate and protein deficiency may occur. 🚨Indigestion of fat due to loss of bile salt absorption. 🚨 Increased fluid/electrolyte loss, leading to watery stools and hence higher dehydration risk.

Large Intestine (Colon)

Absorbs water, vitamin K, biotin, sodium, chloride, potassium, short-chain fatty acids. Normal stool passes through the colon, where water is reabsorbed, and exits through the rectum.

Colostomy impact: 🚨 Reduced water absorption, increasing risk of dehydration (especially in an ascending colostomy). 💡 Descending or sigmoid colostomy → Minimal impact, stool is semi-soft to formed. 🚨 Transverse colostomy → Less water reabsorption, stool is semi-liquid to pasty. 🚨 Ascending colostomy → Significant water loss, stool is liquid or very soft, increasing dehydration risk.