Stool is usually brown because of a balance of bilirubin and bile. Some conditions can cause bright yellow or pale yellow poop or diarrhea. Possible causes include dietary factors, stress, celiac disease, and more.
Stools may change color for various reasons, including a person’s diet and various underlying medical conditions. Yellow is a normal variation of stool color in infants.
Changes in stool color are also normal. Watch for consistent changes over time and consult with a doctor if other symptoms are present.
This article will outline the causes of yellow stool in adults and infants, complications, and when to see a doctor.
A person’s diet and the level of bile present in the stool directly influence a person’s stool color. Bile is yellow-green, and as it travels through the gastrointestinal (GI) tract, enzymes cause changes that turn it brown.
All shades of brown-colored stool are normal. If a person’s stool is red or black, or other changes remain longer than 2 weeks or come with other symptoms, they should consult a doctor.
Stools can be other colors, including:
- Green: Eating leafy green vegetables, green food coloring, iron supplements, or diarrhea moving food through the intestine too quickly may cause this color.
- Yellow, pale brown, or gray: Giardiasis can cause bright yellow diarrhea. Pale yellow or gray stool can result from problems in the liver or gallbladder.
- Orange: Eating carrots, winter squash, antibiotics, or antacids could cause this color.
- Blue: Usually the result of eating artificially blue foods or drinking blue beverages.
- Black, tarry: Eating black licorice or taking iron supplements, and bleeding in the upper GI tract, cirrhosis, or colorectal cancer can also cause black stool. Medication containing bismuth subsalicylate, better known as Pepto Bismol or Kaopectate, can also cause black, tarry stools.
- Bright red: Eating or drinking red, artificially colored food or drinks can cause this. Certain conditions can cause bleeding in the upper GI tract, such as cirrhosis or GI tumors. Hemorrhoids can cause bleeding in the lower GI tract and cause stool to be red.
Possible causes of yellow stool include:
Diet
Since the GI tract processes food for elimination, what a person eats can affect the color of their stool.
Carrots, sweet potatoes, turmeric, and foods that contain yellow food coloring may cause stool to become yellow. A diet high in fat or gluten can also lead to yellow stool.
If a person regularly has yellow stools, they should try avoiding fatty, processed foods, gluten, or anything that causes an upset stomach.
Stress
Stress and anxiety can have many physical effects on the body, including speeding up the digestive process.
As a result, the body may not be able to absorb all of the nutrients in food, which may lead to diarrhea or yellow stool.
Taking steps to relieve stress by reducing commitments, practicing yoga, or seeing a therapist may help reduce physical symptoms.
Celiac disease
If people with celiac disease eat gluten, a protein in wheat, rye, and barley, their immune system responds by attacking the tissues of their small intestine.
This immune response causes tissue damage and compromises the intestines’ ability to absorb nutrients.
In addition to yellow or pale stools, symptoms of celiac disease include:
There is no cure for celiac disease, but a person can effectively manage the condition by avoiding gluten.
Disorders of the pancreas
Disorders of the pancreas can cause yellow or pale stool. Some of these disorders include:
- chronic pancreatitis
- cystic fibrosis
- pancreatic cancer
- blockage of the pancreatic duct
In people with these conditions, the pancreas cannot provide enough enzymes for the intestines to digest food. Undigested fat can lead to yellow stool that also appears greasy or frothy.
Liver disorders
Disorders of the liver, such as cirrhosis and hepatitis, can lower or eliminate bile salts in the body.
Bile salts are essential for the digestion of food and absorption of nutrients. The removal of these salts can result in yellow stools.
Gallbladder disorders
Gallbladder problems and gallstones can also reduce the level of bile salts in the body. This reduction can lead to a variety of symptoms, including:
- abdominal pain
- a fast heartbeat
- an abrupt drop in blood pressure
- jaundice, the yellowing of the skin and the whites of the eyes
- pale stool
Treatment will depend on the specific gallbladder issue. The treatment for gallstones, for example, may include medication to dissolve the stones. In some cases, a person may need surgery.
Gilbert syndrome
Gilbert syndrome is a genetic liver disorder. People with Gilbert syndrome have periods when their bilirubin levels are too high. Symptoms include mild jaundice and pale stools.
However, the symptoms can be so mild that most people do not notice them or know they have the condition.
Giardiasis
Giardiasis is a common intestinal infection caused by a microscopic parasite. A person can contract the Giardia parasite by ingesting Giardia cysts, usually through contaminated food or water.
- stomach cramps
- foul-smelling diarrhea
- yellow diarrhea
- nausea
- fever
- headaches
- weight loss
A doctor can diagnose giardiasis by testing a person’s stool samples.
In infants, shades of yellow, brown, and green are all common stool colors.
In the first week after birth, babies fed human milk will have three or four mustard-yellow, loose stools every 24 hours.
An older adult’s diet or an underlying medical condition may cause yellow stools.
Liver or gallbladder disorders can reduce the production of bile salts, resulting in pale or yellow-colored stools.
If accompanied by diarrhea, older adults should avoid dehydration by drinking water or using oral rehydration solutions.
Yellow stool by itself does not lead to complications, but the underlying cause of it might.
Yellow stool may indicate a malabsorption disorder caused by a parasite, illness, or disease.
Malabsorption of fat
- malnutrition
- weight loss
- vitamin deficiencies
- iron deficiency anemia
- poor bone health
Yellow stool is usually due to dietary changes or food colors. However, if the color change continues for several days or other symptoms are present, it is best to contact a doctor.
A person should see a doctor if they experience any of the following symptoms with yellow stool:
- a fever
- vomiting
- abdominal pain
- pus-filled stool
- inability to urinate
- trouble breathing
- fainting
- a lack of awareness
- confusion or mental changes
Yellow stools are not a typical symptom of irritable bowel syndrome (IBS). However, people with IBS may experience a white mucus in their stool.
Digestive issues that can cause yellow stools include:
- celiac disease
- chronic pancreatitis
- liver disorders
- gallbladder problems
Pancreatic cancer can cause pale or yellow stools that may also appear frothy or greasy due to undigested fat.
Yellow stools are usually due to dietary changes or food colors. However, if yellow stools are accompanied by fever, vomiting, or other symptoms, it is best to contact a doctor
The cause of yellow stool is usually related to a person’s diet, but it can also result from underlying health problems.
Some health problems can lead to malabsorption and malnutrition, which can cause a loss of important vitamins and nutrients.
It is essential to look out for additional symptoms and see a doctor if the yellow color persists. The treatment will depend on the underlying cause.
