Why is my poop green all of a sudden?

A sudden change to green stool is usually temporary and often harmless. Common causes include:

1. Diet (most common)

If you recently ate a lot of:

• leafy green vegetables like spinach, kale, broccoli, or lettuce
• foods or drinks with green coloring

your stool can turn green.

2. Faster-than-normal digestion

Bile is a greenish fluid made by the liver that helps digest fats. Normally, it changes from green to brown as it moves through the intestines. If food passes through too quickly, bile may not have time to change fully, so stool can look green. This is common with:

• diarrhea or loose stools
• stomach bugs or food poisoning
• laxative use

3. Medications or supplements

Some medicines can change gut bacteria and affect stool color. Some supplements, including iron, can also change stool color.

4. Infections

Infections that cause diarrhea can make stool look green because food moves through the gut faster.

What to do

If it’s from food or a short-lived stomach upset, it often goes back to normal within a day or two. Stay hydrated and monitor for other symptoms.

Get medical care sooner if green stool comes with severe abdominal pain, high fever, repeated vomiting, blood in the stool, signs of dehydration, or if it keeps happening for more than a few days.