Home » Health Conditions » Stomach Problems » Diarrhea

What Causes Green Stool?

  • There are several reasons that adults and infants experience light green stool to dark green stool, but for the most part there is nothing to worry about. Most of the time green colored stool is harmless
  • Almost everyone has at one time or another experienced green colored stool during bowel movements. The color can be caused by changes in your diet or an excess in vitamin rich concentrations in your digestive system
  • Green stool in babies can be common and doctors are quick to investigate the child’s diet before offering up a green stool diagnosis
  • Green stool in infants is more common than not and should be looked into further if the green stool symptoms occur over a span of several days or weeks


There are several reasons that people may experience green colored stool in both adults and infants. As always, it is important to consult your family physician for a green stool diagnosis if symptoms progress for lengthened amounts of time. Below are some of the main causes of green stool.

What Causes Green Stool

1. Intake or increased intake of iron supplements

Green in stool can be caused by taking too much or, at times, even adequate amounts of iron. This is especially common in young children. Green stool in babies can be caused by administering liquid iron. Green stool in infants is not harmful but can be alarming to parents, especially first time mothers and fathers when they witness green stool in babies. It is always wise to seek your doctor’s advice when something is out of the ordinary with your child.

2. Medication

Similar to the consumption of certain vitamins or supplements, some medication may cause your bowel movements to be green in color. This can be particularly common in children or infants, as there digestive tracts are more prone to sensitivity. Green stool in babies can occur when the child has a cold and you are administering levels of infant Tylenol or other over the counter medications. Green stool in infants should be monitored and if the symptoms are prolonged you should always consult your doctor. If you notice green in stool after taking medications, like antibiotics, for prolonged periods of time, it is best to consult your physician for a green stool diagnosis.

3. Food poisoning

Green colored stool can be caused by eating foods that are tainted with bacteria, most commonly e-coli. Normally the food and waste will pass quickly, at times just a couple hours after consuming the bad food. It is likely that your bowel movements will contain light green stool or dark green stool. You should always visit your doctor for a green stool diagnosis if the green in stool is visible for more than three days or if you are experiencing abdominal cramps and/or a fever. Green colored stool can be a primary symptom of food poisoning and an indication that something is wrong with your digestive system at the time.

4. Consumption of green vegetables

Green vegetables contain chlorophyll which can cause green stool. Yes, eating too much broccoli for dinner can cause light green stool or even dark green stool. The levels of chlorophyll in most green plants actually turn the color of your stool. This is easy to alleviate by halting the consumption of green vegetables. The roughage, however, is a great source in fiber and works to benefit your colon and digestive system, giving way to more regular bowel movements. Green stool in infants can also be caused by giving your child green vegetables in the form of baby food. The green stool in infants and green stool in babies is not uncommon for this dietary reason.

5. Digestive problems

For the most part green in stool symptoms are not life-threatening and most of the time easy to explain. When there is abnormal digestion taking place you may experience dark green stool or light green stool. When there is green in stool of infants or children for long periods of time, it is important to involve your pediatrician or family doctor.

The information supplied in this article is not to be considered as medical advice and is for educational purposes only.