5 Sneaky Reasons Your Poop Might Be Yellow—and What It Means for Your Gut Health

Let's face it: nobody likes to talk about their poop. However, if you've recently noticed some abnormalities in your poop's shape, texture, or color, it's worth noting and bringing up to your healthcare provider. Why? Well, the state of your poo can say a lot about your digestive health. Thin poop, for example, can signal irritable bowel syndrome (IBS) or a colon blockage, while black poop could be the result of certain foods or medications. But....what about yellow poop? What does this typically mean?

A variety of factors can cause yellow poop, from underlying health conditions to certain lifestyle changes. But before you panic, know that poop color changes are fairly common and not often something to worry about. To get more information, we spoke with a gastroenterologist about the causes, treatment, and prevention of yellow poop, in particular, plus when to see a healthcare provider about poop changes in general.

Why your poop changes color

While most people expect poop to be brown, its color can be influenced by things like diet, gut transit time (i.e., how quickly food and waste move through your digestive tract), bile production (i.e., the liquid produced by your liver that aids in digestion), and the presence of certain types of infections or medical conditions, Sarah Robbins, MD, a gastroenterologist and health consultant based in Canada, tells Well+Good. "The 'normal' brown color comes from bile pigments, which change color as they move through the intestines."

But poop can be a lot of other colors, too, like red, black, green, clay-colored, and yellow. Here's a breakdown of what each one means, according to Dr. Robbins:

• Red poop "can result from eating beets, cherries, or a large serving of red fruits or red food dye," she says. However, she adds that it can also indicate bleeding in the lower gastrointestinal (GI) tract, which could result from conditions like hemorrhoids (swollen veins in or around the anus), diverticulosis (the formation of abnormal pouches in the intestinal wall), or colorectal cancer. If your poop is consistently coming out red regardless of what you eat, you'll want to see your provider.
• Black poop "may be caused by iron supplements, Pepto-Bismol, or dark foods," says Dr. Robbins. "But it can also signal upper GI bleeding caused by conditions like ulcers. By the time blood from the upper GI tract reaches the colon, it breaks down and creates a black, sticky, or tarry stool called "melena." If this happens consistently, see your provider.
• Green poop is "often due to leafy greens, food dyes, or rapid transit of bile through the intestines," Dr. Robbins adds. Rapid transit of bile can be caused by a variety of conditions, including diarrhea, infections, or IBS.¹
• Pale or clay-colored poop suggests a lack of bile flow, which can happen with liver disease, bile duct obstruction, or pancreatitis (i.e., inflammation of the pancreas). Dr. Robbins adds that in her practice, she is most concerned about melena or pale-colored stools because this typically indicates a more serious underlying condition.

5 possible causes of yellow poop

So now, what about yellow poop? Dr. Robbins says that stool with a yellow hue is often caused by fat malabsorption, rapid gut transit, or bile salt (i.e., the main organic substance in bile) issues. "The yellow color of bile comes from bilirubin, which is a pigment derived from heme breakdown in red blood cells," she adds. (For context, heme is a component of hemoglobin—the protein in red blood cells that carries oxygen.)

Once bile makes its way into the gut, Dr. Robbins says it turns brown. However, if bile production or flow is altered, poop may appear yellow due to excess bilirubin or fat malabsorption. With that, here's a breakdown of the five most common reasons your poop comes out yellow.

1. Malabsorption

If fat goes undigested in your intestines, it can interfere with the breakdown of bilirubin, too, says Dr. Robbins, "which can lead to stool appearing yellow." More specifically, it can cause foul-smelling, greasy yellow stool, also known as steatorrhea. A few conditions can cause this, including:

• Celiac disease (an autoimmune condition that causes gut damage from gluten)
• Chronic pancreatitis (persistent inflammation of the pancreas)
• Exocrine pancreatic insufficiency (a condition where the pancreas does not produce enough enzymes to properly digest food)

2. Liver or gallbladder issues

Bile helps break down fats and gives poop its typical brown color. However, when bile production or flow is reduced due to conditions like hepatitis, bile duct obstruction, or gallbladder disease, it can cause stool to appear yellow or pale, says Dr. Robbins. You'll likely have other symptoms with these conditions, like fatigue, fever, and nausea or vomiting, so let your healthcare provider know if you experience anything issues alongside with yellow poop.

3. Infections

Sometimes, certain gut infections can cause diarrhea that moves through your intestines quickly, resulting in yellow poop. The most common infections that can cause this side effect include Giardia (an infection caused by a parasite) and norovirus (a highly contagious viral infection). Both conditions can also cause nausea and vomiting, fever, and fatigue and may require prescription medication for them to resolve.

4. Certain foods

"Large amounts of fatty or processed foods, like turmeric, carrots, or artificial food dyes can sometimes cause yellow stool," says Dr. Robbins. This color change will likely be a little more subtle than other causes and won't typically cause any other gut symptoms.

5. Rapid gut transit

"If bile does not have enough time to break down, excess bilirubin may cause yellow stool," explains Dr. Robbins. Many things can cause rapid gut transit, or the quick movement of waste through your intestines, including stress, anxiety, certain medications (like antibiotics or laxatives), IBS, or inflammatory bowel disease, she adds.

So, should you be concerned if your poop is yellow? In most cases, not really. "As a gastroenterologist, I am rarely concerned about yellow stool," says Dr. Robbins, "as, in most cases, it's transient, diet-related, or due to harmless changes in gut motility rather than a serious underlying disease."

How to treat and prevent yellow poop

Even if yellow poop isn't indicative of a medical emergency, you may still be wondering how to prevent or treat it if it happens to you. Here are some strategies that Dr. Robbins recommends to keep your poop healthy:

• Change up your diet: If dietary fat is a major cause of your yellow poop, try to reduce the amounts of fatty foods (i.e., foods high in saturated and trans fats) you consume. Instead, focus on fiber-rich foods to support digestion and bind to bile.
• Consider enzymes and other medical treatments: If true fat malabsorption is suspected (for example, in pancreatic insufficiency), your healthcare provider might recommend pancreatic enzyme replacement therapy (PERT) to help. This therapy involves taking daily capsules to replace enzymes in your pancreas and improve its overall functioning.
• Get medically evaluated: If a gallbladder or liver problem is suspected, you'll need to get evaluated by a healthcare provider. Through MRIs, stool samples, and other diagnostic work, your provider can determine if medication or a surgical procedure is needed to either remove your gallbladder or treat your liver issues.
• Treat gut infections: If Giardia or another viral infection is suspected, stool testing and targeted treatment like antibiotics or antiparasitics (i.e., medications that kill parasites) may be needed.
• Try probiotics: If an infection caused your poop to become yellow, probiotics may help rebalance your gut bacteria once the infection has cleared.

When to see a healthcare provider

Although yellow poop typically isn't cause for concern, Dr. Robbins recommends further evaluation by a medical professional if you're experiencing any of the following issues:

• Persistent yellow poop lasting more than 2 to 4 weeks.
• Greasy, foul-smelling poop accompanied by unintentional weight loss (which suggests fat malabsorption).
• Yellow poop that's accompanied by jaundice (i.e., a condition when your skin takes on a yellowish tone), dark urine, or pale/clay-colored stools (which suggests liver or gallbladder disease).
• Yellow poop that's associated with severe abdominal pain, vomiting, or other full-body symptoms like fatigue or fever.

Dr. Robbins stresses that if your poop is pale, clay-colored, or yellow, along with dark urine or jaundice, you should seek immediate medical attention, as it could be a sign of a more serious medical condition like liver or gallbladder disease.

The bottom line? "Most cases of yellow stool are temporary, diet-related, or due to gut motility changes," says Dr. Robbins, "and do not indicate serious disease." Unless you're also experiencing concerning symptoms like those listed above, rest assured that adjusting your diet will typically fix the problem.