Why Is My Poo Yellow? 7 Common Causes

TL;DR: Yellow poo can be caused by a variety of factors such as diet, malabsorption, infections, and liver or gallbladder issues. Most causes are harmless but persistent changes should not be ignored.

Overview

If you’ve noticed a change in your bowel movements and are wondering why is my poo yellow, you’re not alone. Changes in stool color can be influenced by many everyday factors, including what you eat, how your digestive system functions, and even infections. Understanding the common causes of yellow poo can help you assess whether your bowel health needs a medical check.

Key Causes of Yellow Poo

Here are 7 common causes explaining why is my poo yellow and what they could mean for your health.

1. Dietary Influences

Certain foods rich in yellow pigments, such as carrots, sweet potatoes, and turmeric, can change your stool color. Fatty or greasy meals may also affect digestion, leading to yellow, greasy stools. If you’ve recently changed your diet, this could explain the yellow appearance.

2. Rapid Transit Time

When stool passes through your intestines too quickly, bile doesn’t have enough time to break down completely. Bile starts off as a greenish fluid that turns brown as it metabolizes. Rapid transit leaves bile yellowish, causing yellow poo.

3. Malabsorption Disorders

Conditions like celiac disease, Crohn’s disease, or chronic pancreatitis can impair nutrient absorption. This sometimes results in pale or yellow, greasy stools due to unabsorbed fats. If yellow poo persists with other symptoms, malabsorption might be involved.

4. Gallbladder or Liver Issues

The gallbladder stores bile used to digest fats. Liver or gallbladder problems, such as bile duct obstruction or hepatitis, reduce bile flow into the intestines. Reduced bile can cause stool to appear yellow or clay-colored. This scenario requires medical attention.

5. Bacterial or Parasitic Infections

Infections caused by bacteria like Giardia or other parasites can cause yellow diarrhea. Such infections often come with cramps, gas, nausea, and fatigue. If you’ve traveled recently or been exposed to contaminated water, this might explain the yellow stool.

6. Medications and Supplements

Certain antibiotics, antacids, or supplements with artificial coloring can alter stool hue. Yellow stool caused by medications is usually temporary but should be monitored if other symptoms occur.

7. Stress and Digestive Upsets

Stress and anxiety can change gut motility and secretions, sometimes leading to yellow stools. While stress alone is less likely to cause persistent color changes, it can exacerbate underlying digestive problems.

When to Seek Help

If you’re asking why is my poo yellow and the change is isolated, it’s often not serious. However, you should consult a healthcare provider if you notice:

  • Persistent yellow stools lasting more than a few days
  • Accompanying symptoms like abdominal pain, weight loss, or fever
  • Pale or clay-colored stools combined with dark urine or jaundice
  • Blood in stool or unexplained diarrhea

Early diagnosis is important to rule out serious conditions such as liver disease, infections, or malabsorption disorders.

Try It Yourself

Curious about your poo color? Try our free poo colour decoder! It’s a simple tool designed to help you understand what your bowel movements might be telling you about your health. Click here to get started!


Understanding why is my poo yellow is a helpful step toward better digestive health. Remember, changes in stool color can often be harmless, but persistent or accompanied symptoms warrant a professional check-up.