Color Changes in Your Baby's Bowel Movements

All new parents develop an unexpected interest in bowel movements and baby poop. Do I worry when the color turns green? Is the milk causing a problem? Is my baby's digestion on track?

Here are the basics to get you through this stage in your baby's life:

What Are Feces?

Your baby's first bowel movement (BM) was called "meconium." This is a thick and sticky residue that is greenish-black in color. You'll never see it again once it passes.

Food in, feces out. Your baby swallows the milk, which is digested by the acids in the stomach and moves into the small intestine. The digested, smaller nutritional elements and water get absorbed into the bloodstream, and the larger, undigested ones (like fiber) keep moving through. If the undigested ones continue down the intestines at a leisurely pace, the water has time to be absorbed and what comes out may be quite firm. Alternatively, if things are moving rapidly, the water has no time to be absorbed and the stools can be quite loose (diarrhea).

As the stool moves thorough the intestines, it also picks up various digestive juices, bile, bacteria, and other chemicals, which impart their characteristic color and odor.

The Effects of Breast Milk vs. Formula

Additionally, what is eaten makes a difference in the final product. Breast milk tends to be absorbed more completely -- sometimes there is so little residue to come out that a baby may not have a BM for days. On the other hand, many breastfed babies pass a mustardy "seedy" yellow stool with each feeding, at least for a short while. Bottle-fed babies tend to have darker and less frequent stools.

Most importantly, every baby is different, and there is a very wide range of what is called normal poop.

Tips for Concerned Parents

Don't be frightened by the color changes of BMs. In normal infants, BMs change color as the baby's diet changes, as the digestive tract matures, and as it is populated by new, normal bacteria. It's rare that color changes signal a digestive problem. Usually color changes just mean that there is more or less of the yellow/green/brown/orange pigments that are picked up along the way.

When to Worry

• If the color of your baby's stools stay chalky white, there may be no bile from the liver to digest the food.
• If the stool is tarry black, there may be blood in the digestive tract that has turned dark black as it traveled down the intestines.
• If there is bright red blood in the stools, there usually has been some blood expressed very close to the anus. A red stool can also be caused by certain medicines, beets, and food colorings. If it's needed, your pediatrician can test your baby's stool to see if blood is present.

You don't need to worry about green, orange, and yellow stools. They are par for the course and are rarely a sign of a digestive problem.