The color of urine - it has an important story to tell
Nutrition Health Review, Fall, 1989


The Color of Urine -- It Has an Important Story to Tell

Definition: The fluid excreted by the kidneys, passed through the ureters,
stored in the bladder and discharged through the urethra. The average
quantity excreted under ordinary dietary conditions in twenty-four hours is
about 1,000 to 2,000 ml. One thousand parts of healthy urine contain about
960 parts of water and 40 parts of solutes, which consist chiefly of urea
and sodium chloride, phosphoric acid, sulfuric acid, and uric acid.

The causes of urine discoloration range from ingested medications to
malignancy.

An abnormal shade of urine can be upsetting to both patient and doctor.
Normal urine color, which ranges from clear to deep yellow, is influenced by
the pigment urochrome. When urine volume is increased the color becomes
pale. From dehydration, the urine tends to be dark. An exception to this
rule would be pale urine present in diabetics with high levels of sugar
being discharged (glycosuria).

Drugs can turn urine red, brown, black, blue, or green. Excretion of some
food colors can result in red urine.

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Colors other than yellow could indicate conditions such as blood in the
urine (hematuria), the result of overexercising and causing myoglobulinuria
(myoglobin in the urine) or aftermath of crash injuries. Also unusual
coloration could reflect pus in the urine (pyuria), a metabolic disorder
(porphyria), or melanoma, a form of cancer.

The most alarming color, red, covers a spectrum of hues from pink to
red-brown. Menstrual flow colorations should not be judged by urine color
standards.

A common laxative ingredient, phenolphthalein, can cause episodes of red
urine. A physician can determine whether that substance is involved. It is
prudent to inform the professional making the urinalysis whether drugs are
being taken.

Various medications may produce red-orange urine. The muscle relaxant
chlorzoxazone (Algisin, Paraflex, Parafon Forte), the antibiotic rifampin
(Rifadin, Rofact), antipsychotics, and some antiparasitic medications may
cause spectacular colorations in urinary discharge.

Some fruits and vegetables, such a blackberries, rhubarb and beets may
temporarily change the color to red. A urinary analgesic, phenazopyridine,
turns acidic urine orange.

Dehydration can cause bright yellow or yellow orange urine. Carrots and
vitamin A turn urine into those colors. So does the vitamin riboflavin.

Medications that cause a yellow-brown urine include quinine derivatives and
two drugs that are used to treat urinary tract infections: nitrofurantoin
and sulfamethoxazole.

Colorless urine is often the result of diuretic use or high fluid intake,
which can be harmless. Diabetes insipidus is associated with colorless
urine, the ingestion of ethyl alcohol, and hypercalcemia, a condition caused
by too much calcium in the system because of faulty metabolization.

Milky urine can result from high levels of fats in the body. Cloudy urine
commonly indicates the presence of a urinary tract infection.

Most blue or green urine can be caused by chlorophyll-containing foods such
as breath mints (Clorets); magnesium salicylate, found in Doan's Pills, and
in cough remedies; and thymol, an ingredient in Listerine.

Cresol and phenol, found in Chloraseptic, may cause a brown or yellow-green
color that darkens on standing.

Vitamin C in large doses colors urine bright yellow and diminishes as the
vitamin leaves the body.

Because urine coloration ranges widely, the concerned individual should
consult with a physician to determine whether foods, drugs, chemicals, or
infections are involved. In a healthy individual, food variations may be the
sole determinant