It’s probably not much surprise that the color of poop can reveal certain things about our health. For example, if your stool is green, it may indicate that food moves through the large intestine too quickly; if it becomes a pale white, or clay-like color, it may indicate a lack of bile; yellow, undigested fat. Black or red indicates blood in your stool and you should seek medical attention immediately. The insight that stool color provides doesn’t stop there. The next 7 weird facts about stool color may tell you more about poop than you’d like to know but can provide valuable health information.
1. It Can be a Health Monitor for Infants
Baby poop is a barometer for parents to monitor their newborn’s health. Until a child starts on solid food, poop color should be a consistent color and texture with deviations indicating potential health problems. Breast-fed babies should have yellow stools; formula-fed babies should have green.  Babies with neonatal liver disease will have darker color stools as a result of excess bilirubin.  And as babies get older poop color may change reflecting food sensitivities and allergies, such as milk-allergy or lactose intolerance.
In the same way a baby’s stool reflects health changes, a change in adult stool color can inform about the impact of medications on ones system and potential health concerns…
2. Medications Can Affect Stool Color
Just as dietary changes will alter stool color, so does medication. Antibiotics can change stool color by altering the balance of bacteria in the gut and impacting digestive process. But antibiotics aren’t alone. A common method for addressing constipation in pregnant women is xylooligosaccharides, a prebiotic derived from grains. It causes bifidobacterium (friendly gut bacteria which aid digestion) to increase in number and help relieve constipation. It also causes stool color to turn from dark brown to a yellow brown. 
3. Mixed Medications Can Produce a Rainbow Effect
An alternative to penicillin, cefdinir, given to infants with ear infections has been found to mix with iron-containing supplement and create indigestible compounds containing iron. The result, red colored stool.  Discontinuing the medication resolves the distressing stool color.
4. Surgery Can Affect Stool Color
Surgical changes to the small intestine can change the way digestion works. Patients with Short Bowel Syndrome, where all or portions of the small intestine have been removed, experience dramatic changes to digestion and stool output. The stool color may change to a consistent green as a result of incomplete digestion and nutrient absorption. While average bowel transit times is around 12 hours+, bowel transit for patients with Short Bowel Syndrome may be as low as 90 minutes.  
5. Harmful Organisms Create Unusual Stool Hues
A cross-sectional study from Thailand looked at the impact of harmful organism infestation on stool color. While stool consistency was the most consistent change, a trend to unusual stool colors was also observed. These unusual colors included red-brown, red-orange, green, black or grey.  That brings us back to a good rule to follow, if red or black in stool, see a health care professional immediately.
6. If You’ve Eaten Beets…
14% of the human population is susceptible to beeturia, a condition that occurs when the human colon absorbs the red dye from beets. In turn, stool and urine will take on a red hue.  If you regularly eat a lot of beets (they are great for your health!) you’ve probably experienced this.
7. Radiation = Blue Poo
Exposure to radioactive cesium and thallium requires immediate medical attention. Prussian Blue is a pill given to expedite removal of these radioactive elements in the intestines. One of the side effects? Stool turns blue. 
Stool color can fluctuate with diet and medication. When a color change occurs to an unusual color and becomes consistent, it may be time to seek the input of a trusted professional. For the best digestive health, and stool color, eat natural foods, especially those with probiotic and prebiotic properties.
-Dr. Edward F. Group III, DC, ND, DACBN, DCBCN, DABFM
- den Hertog J, van Leengoed E, Kolk F, van den Broek L, Kramer E, Bakker EJ, Bakker-van Gijssel E, Bulk A, Kneepkens F, Benninga MA. The defecation pattern of healthy term infants up to the age of 3 months. Arch Dis Child Fetal Neonatal Ed. 2012 Nov;97(6):F465-70. doi: 10.1136/archdischild-2011-300539. Epub 2012 Apr 20.
- Emerick KM, Whitington PF. Neonatal liver disease. Pediatr Ann. 2006 Apr;35(4):280-6.
- Tateyama I, Hashii K, Johno I, Iino T, Hirai K, Suwa Y, Kiso Y. Effect of xylooligosaccharide intake on severe constipation in pregnant women. J Nutr Sci Vitaminol (Tokyo). 2005 Dec;51(6):445-8.
- Lancaster J, Sylvia LM, Schainker E. Nonbloody, red stools from coadministration of cefdinir and iron-supplemented infant formulas. Pharmacotherapy. 2008 May;28(5):678-81. doi: 10.1592/phco.28.5.678.
- Medline Plus. Bowel Transit Time. (last accessed (2013-12-21)
- Compher C, Rubesin S, Kinosian B, Madaras J, Metz D. Noninvasive measurement of transit time in short bowel syndrome. JPEN J Parenter Enteral Nutr. 2007 May-Jun;31(3):240-5.
- Saksirisampant W, Prownebon J, Saksirisampant P, Mungthin M, Siripatanapipong S, Leelayoova S. Intestinal parasitic infections: prevalences in HIV/AIDS patients in a Thai AIDS-care centre. Ann Trop Med Parasitol. 2009 Oct;103(7):573-81. doi: 10.1179/000349809X12502035776072.
- Eastwood MA, Nyhlin H. Beeturia and colonic oxalic acid. QJM. 1995 Oct;88(10):711-7.
- CDC. Prussian Blue. (last accessed 2013-12-21)