Color of Urine

The Color of Urine Can Reveal Much About Health: Understand What Each Color Means

Urine color can vary widely in different shades, such as red, yellow, pink, green, purple, orange, and blue, in addition to other unusual colors. It plays an essential role in eliminating waste from the body, such as urea, creatinine, and red blood cells, as well as excreting ingested compounds, such as vitamins and medications. Urine color is an important clinical indicator as it can assist doctors in diagnosing potential health problems.
Red Urine
Red-colored urine usually indicates the presence of blood in some part of the urinary tract, which includes the kidneys, bladder, prostate, and their connecting ducts. The shade of blood in the urine can vary depending on the amount and how long the blood has been exposed, sometimes acquiring a color similar to red wine in cases of more intense bleeding.
This symptom may be related to various medical conditions, such as kidney stones, cancers, injuries, and urinary tract infections. Additionally, red urine can result from consuming excessive amounts of pigmented foods like beets, which can give the urine a reddish hue, although this is harmless.
Yellow Urine
Normal urine color varies between shades of yellow, which primarily depend on the individual's hydration level. Dehydration can make urine darker, sometimes almost orange, while proper hydration results in lighter urine. Urobilin is the compound responsible for urine's yellow color. This pigment is a byproduct of the breakdown of aging red blood cells.
The decomposition process of red blood cells generates bilirubin, which is excreted through both urine and feces. When there are issues with bile flow, such as in cases of gallstones or cancers that block bile ducts, bilirubin is reabsorbed into the blood and eliminated through the urine, resulting in a darker color, like orange or brown tones. This condition, called obstructive jaundice, can also cause yellowing of the skin. Furthermore, some medications, such as the antibiotic rifampicin, can turn urine orange.
Green or Blue Urine
Though rare, green and blue urine colors can surprise people. These shades can result from consuming foods or beverages containing dyes of these colors. Certain medications, such as antihistamines, anesthetics, and vitamin supplements, can also cause this alteration.
Some bacterial infections, such as those caused by Pseudomonas aeruginosa, can also lead to green-colored urine. This bacterium produces compounds that change urine color and cause urinary tract infections, often accompanied by fever or discomfort during urination.
Purple Urine
Purple or indigo-colored urine is extremely rare. A possible cause is porphyria, a genetic condition that affects the skin and nervous system, characterized by the overproduction of porphyrins, which result in purple-colored urine.
Another condition that can cause this color is purple urine bag syndrome. This condition occurs in patients who use catheters and is caused by bacteria that degrade compounds in the urine, leading to the formation of purple pigments.