Why Is My Stool Yellow and Foamy? 11 Causes

1. Giardiasis

Giardiasis is a parasitic infection that can cause yellow and foamy stools. The infection is typically contracted by eating contaminated food or water. Other symptoms of giardiasis may include:

• Yellow diarrhea
• Stomach cramps
• Nausea
• Headaches
• Fever

2. Chronic pancreatitis

Chronic pancreatitis disrupts your ability to digest fats. Undigested fats can turn the stool yellow and foamy. It can also lead to severe upper abdominal pain that can spread to the back. Pancreatitis may be caused by:

• Gallstones
• Alcohol misuse
• Pancreatic cancer
• Genetic disorders of the pancreas

Apart from yellow and foamy stools, other symptoms of pancreatitis include:

• Nausea
• Fever
• Increased heart rate
• Vomiting
• Bloating

3. Pancreatic cancer

Pancreatic cancer can also disrupt the function of the pancreas, which is responsible for producing digestive enzymes. If food in your digestive tract remains undigested, it can lead to yellow and foamy stools. Some of the risk factors for pancreatic cancer include:

• Tobacco use
• Heavy alcohol consumption
• Diet high in processed foods
• Chronic and hereditary pancreatitis
• Obesity
• Diabetes

Other symptoms of pancreatic cancer include:

• Loss of appetite
• Unintentional weight loss
• Blood clots (often in the legs, which can cause redness, pain, and swelling)
• Jaundice (yellowing of the skin and eyes)
• Depression
• Dark or brown urine
• Itchy skin
• Nausea
• Vomiting
• Abdominal pain, which may radiate to your back
• Lower back pain

4. Celiac disease

Celiac disease is a type of malabsorption disorder. When a person with celiac disease consumes gluten found in wheat, rye, and barley, their immune system attacks and damages the tissues of their small intestine. As a result, their body cannot fully digest and absorb essential nutrients from foods, which can lead to yellow and foamy stools. Some of the most common symptoms of celiac disease include:

• Diarrhea and/or constipation
• Nausea
• Bloating
• Loss of bone density
• Depression
• Fatigue
• Headache
• Skin rash

5. Liver and gallbladder disorders

Yellow stools can indicate a lack of bile, which usually gives the brown color to normal stools. Certain conditions can reduce the level of bile salts in the body, which are responsible for the digestion of food and absorption of nutrients. These conditions may include:

• Liver cirrhosis
• Hepatitis
• Gallstones
• Sludge in the gallbladder

6. Gilbert syndrome

Gilbert syndrome is characterized by high bilirubin levels, mild jaundice, and yellow stools. Symptoms are often so mild that the condition goes unnoticed and untreated. 

7. Stress and anxiety

Stress and anxiety can speed up the digestive process, which makes it difficult for your body to absorb nutrients in food. This can lead to yellow stools and other gastrointestinal symptoms like diarrhea.

8. Diet

Foamy stools can be caused by a high-fat diet. Foods that can cause yellow or foamy stools may include:

• Carrots
• Sweet potatoes
• Foods high in food color
• Gluten products

9. Irritable bowel syndrome (IBS)

A disorder of the digestive tract, IBS can lead to mucus in the stools, which causes the stools to appear foamy. Other symptoms of IBS include:

• Abdominal pain
• Changes in bowel movements
• Alternating diarrhea or constipation
• Bloating

10. Abdominal surgeries

Abdominal surgeries that remove a section of the small or large intestine can lead to short bowel syndrome, which often causes chronic diarrhea and foamy stools. This is usually temporary and resolves as the body heals from the surgical procedure.

11. Lactose overload in breast milk

Foamy stools in babies are usually caused by lactose overload in breast milk. Breast milk is made of up foremilk and hindmilk. Foremilk is the initial thin milk that comes out as the baby begins to feed. It has fewer nutrients and can cause the baby to have stool changes if they are getting too much.