Why Beets Cause Redness in Stool and Urine? The Science Behind This Surprising Phenomenon

Beets offer numerous health benefits, including increased energy, enhanced brain function, and improved immune system support. However, eating beets can lead to surprising changes in stool and urine color, with beeturia affecting approximately 14% of the population.

What Causes Beets to Change the Color of Urine and Stool?

The reason behind this phenomenon lies in betanin, the reddish-purple pigment responsible for the vibrant color of red and purple beets. Whitney Linsenmeyer, an assistant professor of nutrition and dietetics at Saint Louis University in Missouri and a spokesperson for the Academy of Nutrition and Dietetics, explained that this pigment is not present in golden beets, which instead contain yellowish pigments called betaxanthins.

Beyond its role as a pigment, betanin also serves as a potent antioxidant, capable of neutralizing harmful molecules known as "free radicals" within the body. By stabilizing free radicals, betanin may help prevent damage to DNA and other cells while possessing anti-inflammatory properties, according to Linsenmeyer.

However, the body's ability to absorb betanin is limited due to its low bioavailability. This pigment resists digestion, and only a small fraction of the ingested betanin can be absorbed by gut cells. Studies have suggested that approximately half of ingested betanin gets broken down, primarily in the intestines.

The remainder of unmetabolized betanin is excreted through the digestive tract, leading to the reddish or pink discoloration of poop. Linsenmeyer stated that this is a normal reaction observed in roughly one in ten people, with this statistic originating from a 1963 study.

This condition, known as beeturia, occurs when unprocessed betanin passes through the kidneys and into urine, often accompanying the reddening of a person's stool. Beeturia is generally considered benign, lasting only a few hours after beet consumption.

While earlier research suggested genetic or iron deficiency links to beeturia, recent studies have shown that it primarily arises from the body's limited capacity to metabolize betanin, as outlined in a 2021 review.

Treating Beeturia

Beeturia is typically harmless and doesn't necessitate specific treatment. However, if an underlying condition contributes to the color change in urine, medical guidance should be sought for appropriate management.

In instances where iron deficiency or low stomach acid causes the alteration in urine color, addressing the underlying issue is essential to mitigate beeturia. Iron deficiency anemia resulting from internal bleeding might require diagnostic procedures such as pelvic ultrasounds, endoscopy, or colonoscopy to identify the bleeding source in areas like the stomach, rectum, or pelvis.

When conditions like heavy menstrual cycles or ulcers are responsible for iron deficiency, treatments could involve doctor-prescribed antibiotics, contraceptives, or surgical interventions to remove bleeding tumors or fibroids. In cases unrelated to internal bleeding, iron supplementation may be recommended to stimulate red blood cell production.

For individuals with low stomach acid due to medications like H2 blockers or proton pump inhibitors (used for acid reflux), reducing medication dosage may aid in increasing stomach acid levels. Additionally, healthcare providers might suggest digestive enzymes, such as Betaine HCL with pepsin, to enhance stomach acidity.

In cases where beeturia isn't linked to underlying conditions and other causes have been ruled out through testing, consuming extra water can boost urine output and expedite the elimination of the beet pigment from the body.