Colon

Definition

Terminal part of the large intestine, approximately 1.5 meters long, responsible for the absorption of water, electrolytes, and the formation of stool by reabsorption of residues.

How it works

The colon receives undigested food residues from the ileum. Its primary role is to extract water and electrolytes (such as sodium and potassium) from food residues, allowing the body to remain hydrated. The colon also houses an important bacterial flora (microbiome) that produces short-chain fatty acids, synthesizes certain vitamins (including vitamin K), and plays a key role in immunity. Concentrated residues form stool, which is stored in the rectum before elimination. Good colon health depends on a fiber-rich diet and a balanced microbiome.

Role

Absorb water and electrolytes, host the microbiome, form, and store stool.

Examples

• Water reabsorption from intestinal chyme
• Vitamin K synthesis by bacteria
• Stool formation

Recommendations

Consume 25-35 grams of fiber per day to support colon health. Drink enough water to promote regular transit. Include fermented foods or probiotics to maintain a healthy microbiome.

Key takeaway

The colon is essential for bodily hydration and hosts a vital microbiome for health.

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