Stool color: yellow, black, green, red, the sign of what? solutions?

Stools, also called feces, or feces, are made up of the residues from our digestion that have not been absorbed by our intestines. They are composed of 75% water and 25% mucus, bacteria and other intestinal cell debris.

There is no standard in terms of frequency: transit varies greatly from one person to another. Some have a bowel movement three times a day, while others only go once every two or three days. On average, according to the French National Society of Coloproctology, we pass 150 g of stool per day (source 1). Either way, the expulsion should be easy and painless. As for the color of the stool, it can be influenced by many factors.

In healthy adults, stools are usually brown in color, with more or less light shades. This color is linked to the degradation of bile (which allows the breakdown and absorption of fats), released by the liver via the bile ducts in the first part of the intestine, the duodenum. All element that will disrupt this cycle of degradation natural therefore impacts the color of the stool. Among the main factors:

• food,
• medication,
• a change in lifestyle,
• transit acceleration,
• the presence of a virus, bacteria or intestinal parasite,
• etc

Yellow-colored stools can be a sign of a digestive pathology. They indicate the presence of undigested fats. In this case, they will often be accompanied with a greasy texture and fetid odors. We speak of steatorrhea when the amount of fat in the stool exceeds 6 grams per 24 hours.

This phenomenon may be related to a fat malabsorption as in celiac disease (gluten intolerance), Crohn’s disease or certain diseases of the pancreas. The yellowish color may also indicate that you produce too little bile, due to a blockage in your gallbladder. The Gilbert’s diseasewhich is characterized by liver dysfunction, can also cause an abnormal rise in bilirubin (yellow pigment produced by the breakdown of hemoglobin), toxic to the body when present in excessive quantities.

Light beige or whitish stools indicate a defect in the flow of bile in the intestine. This may be related to a blockage in the bile ducts (gallstones of the bile ducts, tumor of the pancreas, etc.) or hepatitis.

Orange stools can be linked to excessive consumption of beta-carotenean antioxidant plant pigment, found in some food supplements, but also in vegetables such as carrots, sweet potatoes, squash, some leafy green vegetables and some herbs.

Red stools may be related to consumption of foods such as beetsor any food containing the red dye.

But it can also be traces of blood relating to a bleeding in the lower part of the digestive tract, resulting from inflammatory bowel disease, internal or external hemorrhoids, anal fissures, polyps or even colorectal cancer or rectal cancer. This is why in doubt, from the age of 50, it is better to perform a colonoscopy, even if it only happens once.

Several foods can color the stools black, especially those that are rich in iron, such as spinach, beets, black pudding, etc. In this case, there is therefore nothing to worry about. However, the black color can also be explained by:

• medications, or iron-rich food supplements which will be oxidized by digestive juices and give a black color;
• some charcoal treatments ;
• a severe constipation : in this case, the stools that have stagnated a lot in the intestine may be black or very dark brown;
• a gastrointestinal bleeding superior (in the esophagus, stomach or small intestine);
• gastroesophageal reflux Where a peptic ulcer (a deep wound located in the inner lining of the stomach or in the first part of the intestine, the duodenum). In this case, the stools are very black, pasty and smelly.

Green stools are usually a sign of too much consumption of green foodssuch as leafy green vegetables (cabbage, spinach, etc.) or foods containing chlorophylla green dye (basil, parsley, mint, etc.).

Iron supplements and spirulina can also turn faeces green.

The green stools also testify to an acceleration of the transit, in the case of a gastroenteritis (bacterial or viral) for example, or a acute diarrhea. Bile does not have time to be broken down by the intestinal flora and remains green if it moves too quickly.

First of all, it must be checked that the color of the excrement is not linked to the unusual consumption of certain foods. If this is the case, and it appears punctually (a day or two), there is no need to worry. Likewise if the color of the stools is linked to taking medication or food supplements.

However, if the color is not associated with food and persists, or repeats regularly, it can be the sign of a pathology of the liver, the gallbladder, the intestine, a problem of transit, digestion, or hemorrhage (as mentioned earlier). It is therefore better to consult a doctor quickly to determine the cause of this coloration and eliminate any risk of serious pathology. Similarly, if one or more members of your family have been affected by digestive cancer.

In the first place, consult your doctorwho will consider further explorations and consultation with a gastroenterologist.

Then, the diagnosis is most often based on stool analysis : in the event of haemorrhage, examinations must be carried out to determine the cause and the exact location of the anomaly: digital rectal examination, colonoscopy and anoscopy, etc.

The treatment, meanwhile, is said to be etiological. : it depends on the cause of the color of the excrement. Depending on the origin, we can bet on antibiotics against bacteria, intestinal antiparasitics, cream against hemorrhoids, etc. In case of cancerous tumor, a surgical operation will be necessary.