Have you ever looked in the toilet and wondered, “Why is my poop green? Or yellow?”

You're not alone — stool color is one of the most Googled digestive health questions. I get a lot of questions about the color of people’s stool, so I wanted to cover some the most common issues for you in this video.

What Is Normal Stool Color?

The most common and “normal” stool color is medium to dark brown. This is primarily due to a pigment called bilirubin, which is a byproduct of a normal red blood cell breakdown process by your liver, and when it mixes with bile. And healthy bacteria also play a role in this color.

When your stool color changes, this can be a helpful clue about what’s going on inside your body.

What Does Green Stool Mean?

🥗 Common Causes of Green Stool:

1. Diet – Eating a lot of leafy greens like spinach, kale, or foods with green food coloring (think sports drinks or frosting), can turn your stool green.

2. Digestive Speed – Meaning, too much bile in your stool.  When food moves too quickly through your digestive tract (like during diarrhea), bile doesn’t have time to be reabsorbed completely, and the result can be green stool.

3. Iron Supplements – Taking iron can sometimes cause your poop to turn green or even blackish green.

4. Gut Imbalance or Infection – Certain bacterial infections or an imbalance in your gut microbiome can also lead to greenish stool.

✅ When Green Stool Is Usually Not a Problem:

If you feel fine and the green color goes away in a few days, it’s probably diet-related or just temporary.

🚨 When to Be Concerned About Green Stool:

• If you also have diarrhea, cramping, fever, or other digestive problems

• It’s happening frequently and unexplained by diet

• It’s accompanied by foul odor or other symptoms

What Does Yellow Stool Mean?

🌽 Common Causes of Yellow Stool:

1. Fat Malabsorption – The most common reason for yellow, greasy, or foul-smelling stool is your body not digesting fat properly. This may point to conditions like:

o Celiac disease or gluten intolerance.

o Other food intolerances

o Pancreatic insufficiency (as in chronic pancreatitis, amongst many other causes)

o Bile acid deficiency (Such as after gallbladder removal. Although ironically, gallbladder removal can also cause too much bile, not too little.)

2. Giardia Infection – This parasite can cause yellow diarrhea, fatigue, and bloating.

3. Other Liver or Gallbladder Issues – If bile production or flow is impaired, stool may appear pale yellow or clay-colored.

🟡 Characteristics of Yellow Stool:

• Oily or shiny in appearance (often floats), and often will streak the toilet bowl because it’s sticky.

• Strong, foul odor

• Accompanied by bloating, gas, or stomach discomfort

🚨 When to Be Concerned About Yellow Stool:

• Persistent yellow stool over weeks

• Significant weight loss, fatigue, or nutritional deficiencies

• Recent gallbladder surgery, IBS, or digestive illness

Other Stool Colors You Should Know About:

• Black Stool – May indicate bleeding in the upper GI tract or be due to iron supplements.

• Red Stool – Could mean bleeding in the lower intestine or rectum (like hemorrhoids or polyps) or just be from eating beets.

• Pale or Clay-Colored Stool – Often a sign of bile duct obstruction or liver/gallbladder problems.

When to See a Doctor

If your stool is green or yellow occasionally and goes back to normal, it’s probably harmless.

But if you experience:

• Ongoing changes

• Weight loss

• Chronic digestive problems lasting more than a month

• Signs of nutrient malabsorption

Then it’s time to find out what is causing it. These are all treatable. So make sure that you get answers. Because if you aren’t getting better, then you aren’t seeing the right doctor.

And if there are any unexplained signs of black or red stool, then be sure to get that checked out, because you want to find out if it’s blood.

Final Thoughts: Trust Your Gut (Literally)

The color of your stool can be a useful indicator of your digestive health. Green and yellow stool are among the most common stool questions — and while often harmless, they can signal deeper issues that are worth addressing.

Related Content:

Bile Acid Malabsorption and Bile Acid Deficiency After Gallbladder Removal

Understanding the Side Effects of Steroids

Gut Motility Isn’t the Problem. Here’s What Is.

The Truth About Bloating and Fizzy Drinks‍