Contents of stool in humans is mainly water (about 75%), dead bacteria that helps in breakdown of food, some living bacteria, protein, fiber that is undigested, waste materials from food, cellular linings, salts, fats and other substances released from intestine.
Appearance of stool:
Stools are usually brown in colour, due to the bile content. Bile is the fluid secreted by liver that helps in digestion of fats. Originally, bile is yellowish-green in color but once they travel through the intestine and breakdown fats, the bile turns brown in color and is passed out through the stool or feces.
The color of the stool also depends on what is eaten. Color of the stool may come from eating green leafy vegetables like spinach or kale, iron supplements, food coloring used in drinks or ice pops, beets, tomato soup, gelatin desert, Vitamin B6 supplements and others.
|Color of stool||Normal causes||Pathological conditions|
|3.||White or pale colored||
Types of stool:
Stool comes in 7 different textures according to the condition of the digestive tract. Meconium is the first stool that a newborn passes. The seven types of human adult stools are:
- Separate hard lumps, hard to pass is a sign of constipation.
- Sausage-shaped but lumpy also suggests constipation.
- Sausage-shaped by with cracks on surface
- Sausage-shaped, smooth and easy to pass
- Soft blobs with clear-cut edges
- Fluffy pieces, mushy stool
- Watery or semisolid stool.
Odor of stool:
Stool gets the typical odor from its contents such as methyl sulfides, benzopyrrole volatiles and hydrogen sulfide. These chemicals come from the diet such as meat protein and dairy products. Herbs such as rosemary also contribute to the odor. Various processes of digestion and the amount of time the undigested food stays in colon also determine the odor of the stool.
Contents of stool:
An average healthy human adult eliminates around 130 grams of fresh stool per day with a pH value of about 6.6. The typical stool contains 75% of water. The remaining solid fraction contains:
- 25-54% bacterial biomass
- 2-25% protein or nitrogenous matter
- 25% carbohydrate or undigested plant matter
- 2-15% fat
- Calcium and iron phosphates
- Intestinal secretions
- Dried epithelial cells
Undigested foods in the stool include:
- Seeds, nuts and corn
- Natural or artificial colors in food