Sunday, November 25, 2012

Rainbow urine? Urine analysis in medicine over the centuries

17th century print of a physician analyzing a patient's urine

Urine is the way that we get waste products in our bodies, out of it. Generally, we're quite happy to flush it away, except for those unpleasant times when we have to maneuver in such a way as to pee in one of the dreaded sample cups. As an EMT, one of the bad things we’re told to watch out for is“coffee grounds” in the urine (indicative of internal bleeding). Dark urine is indicative of dehydration. Other things to watch out for are things like really sweet-smelling urine, which is indicative of diabetes. Most of the analysis work in clinics and hospitals is done by electronic sensor arrays, a complex set of electronic equipment that can breaks down the chemical composition of the urine. Yet urine analysis was around long before there were complex technologies to do it.

Of traditional Asian medicines, urine analysis is a diagnostic tool that is relatively unique to Tibetan medicine. Chinese medicine did not pick it up until later, and Indian Ayurvedic medicine only uses it when diagnosing urinary diseases. One of the oldest extant Tibetan texts, The Lunar King, describes in great detail how to analyze urine by observation, to analyze the connections between urine, disease, and evil spirits, and how to engage in “urine divination.” The text is quite extensive, detailing analysis down to when and where the urine should be analyzed (at first rays of light, indoors), the container it should be analyzed in (no color), and the patient’s responsibilities before the urine sample is taken (moderate drinking, no sex, no white, yellow, or red drinks, no strong-tasting foods).

Once these conditions are set up, the color of the urine is examined. A few of the possible diagnoses are:

                        -Red indicates excessive blood

-Reddish-yellow indicates excessive lymphatic fluid

-Dark red indicates infectious disease from excessive blood

-Very yellow indicates bile

-Brown or bluish yellow is from phlegm

                        -Black indicates lymph and wind

                        -Green indicates cold.

                        -Brightness (“rainbow colors”) is cold and poison

The analysis also includes looking at smell, sediments, and whether the urine divides into layers over time. Urine analysis continues to be one of the primary markers of Traditional Tibetan Medicine.

While the Tibetans were analyzing urine on one side of the planet, the Greeks, the Arabians, and the Byzantines were also very interested in urine as a diagnostic tool, looking at much the same things that the Tibetans were: color, smell, sediment.

Urine analysis continued in western medicine as well for centuries. The following graphic is from the book Epiphanie Meidcorum by Ullrich Pinder, published in 1506. This graphic helps instruct physicians how to diagnose diseases from the varying colors of the urine. Like in Tibetan medicine, health in the western world was viewed as being a balance between different Humors. In Tibetan medicine, there are three: in Western medical systems, there are four. Abnormally colored urine indicates that the humors are out of balance--too much blood, perhaps, or too little lymph.

I actually have no idea what might cause dark green urine, but I have the feeling, if you see that in the toilet, you should probably go to a hospital.


  1. I have started eating beets from our CSA box so much more frequently now. The result is pink to red urine, which was initially extremely alarming, as you can imagine. Beeturia. It's a real thing. Check it out on wiki sometime.

  2. I actually think asparagus might result in green urine...and it usually gives it a really peculiar smell