Urine isn't something most people talk about. We barely give it more than a passing glance as it swirls out of sight down the toilet bowl. Yet changes in the urine -- its color, odor, and consistency -- can provide important clues about the status of your body. Your urine can reveal what you've been eating, how much you've been drinking, and what diseases you have.
"Urine and urinalysis have, for hundreds of years, been one of the ways physicians have looked at health," says Tomas Griebling, MD, MPH, vice chair of the urology department at the University of Kansas.
"From a historical view, urinalysis was one of the original windows into what's happening in the body," Griebling says. That's because many of the substances circulating in your body, including bacteria, yeast, excess protein and sugar, eventually make their way into the urine.
Urine is an important part of the body's disposal process. Its job is to remove the extra water and water-soluble wastes the kidneys filter from the blood. "The urine is there primarily to get rid of toxins or things that would otherwise build up in the body that would be bad for the body," says Anthony Smith, MD, professor and chief of urology at the University of New Mexico.
When you notice that your urine has changed color, or there's a strange odor wafting up from the toilet, the cause might be something as harmless as what you had for dinner (which could have included beets or asparagus). It also might be a sign of a more serious condition, such as an infection or cancer.
Before you flush, here are a few urine changes to look out for, and what they might be saying about your health.
Urine gets its yellow color from a pigment called urochrome. That color normally varies from pale yellow to deep amber, depending on the concentration of the urine. Darker urine is usually a sign that you're not drinking enough fluid. "Your body needs a certain amount of fluid to function, so the body will hold on to fluid and the urine will become very strong and concentrated. When that happens, it will turn a darker color," Griebling says.
The opposite is also true. If your urine is very pale, it means that you're either drinking a lot of fluid, or you're taking a diuretic -- a drug that forces the body to get rid of excess water.
Urine can turn a rainbow of colors, and an unusual hue isn't necessarily cause for alarm. Certain medications can turn the urine fluorescent green or blue, carrots can tint it orange, vitamins can give it a yellow hue, and an inherited disease called porphyria can shade it the color of port wine.
Seeing red is typically a sign that there is blood in the urine, but before you panic, know that a little blood can produce a dramatic color change. "What I always tell patients is it takes one drop of blood to turn a toilet bowl red," Smith says.
That said, just a little blood in the urine can be a sign of something serious, like an infection or cancer, and it warrants a visit to your doctor or urologist. If you're seeing blood and your urine is also cloudy, there's a good chance you've picked up an infection, Smith says.