The color of stool normally is brown. The reason for the brown color is the presence of bile in the stool. Bile is made by the liver, concentrated and stored in the gallbladder, and secreted into the intestine to aid in the digestion of food. Depending on the amount of bile it contains, the normal stool color can range in color from light yellow to almost black.

Bile secreted from the gallbladder into the intestine is a very dark green liquid made up of many chemicals, one of which is bilirubin. When red blood cells are destroyed naturally in the body, the hemoglobin, a protein inside the red blood cells that carries oxygen, is modified in the liver. The by-product of this process is bilirubin, and the liver secretes the bilirubin into bile.

As bile travels through the intestines, it can undergo further chemical changes, and its color can also change. For example, if the traveling time through the intestine is rapid, then bile won't have the time to go through additional color changes and the stool color may be close to green.

The color of stool can change for other reasons as well. Many changes in stool color may not be of much importance, especially if the change happens once and is not consistent from one stool to the next. Sudden major changes in stool color that persist may suggest an underlying medical problem. Furthermore, gradual but persistent changes in stool color also can signify medical problems.

Some of the important colors of stool that can signify problems include: red, maroon, black, clay-colored, pale, yellow, green, and even white when taking certain medications.

no, it's colorless and transparent, you can' t see it. now you don't.