Your kidneys cleanse all of the blood in your body about every 50 minutes.

Your body forms several kinds of waste, including sweat, carbon dioxide, feces, and urine, each with a system for eliminating it from the body. The urinary tract is one part of the body’s very sophisticated cleansing system.

The urinary tract filters excess fluids and other substances from your blood. Your urinary tract is made up of your kidneys, ureters, bladder, and urethra. As your body works, it creates chemical waste products it can’t use. The chemical wastes that end up in your blood stream are filtered through your kidneys. Your kidneys provide a filtration system that sends about 99 percent of your blood back into your system, while sending the waste to your bladder for storage and later disposal. Your kidneys receive about 120 pints of blood per hour (or 440 gallons of blood daily), filtering out the waste and making sure the returning blood has the right proportions of water, vitamins, minerals, etc. Your kidneys cleanse all of the blood in your body about every 50 minutes.

Once the kidneys have done their jobs, the filtered liquid waste (urine) travels down the ureters to the bladder where it is stored. Your bladder can stretch to hold as much as a pint of urine.

When your bladder becomes full, it sends a message to your brain that it’s time to empty your bladder. When that happens, the muscles in the wall of the bladder contract, forcing urine into the urethra, which transports it from the bladder to the outside of your body.

A normal adult passes about a quart and a half of urine each day. The volume formed at night is about half that formed during the day. Normal urine contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.

Urinary tract infections 

• Each year, urinary tract infections account for about nine million doctor visits.
• Urinary tract infections occur more frequently in women than men. One woman in five develops a urinary tract infection during her lifetime.
• Urinary tract infections in men are not as common, but can be serious when they do occur.

Any abnormality of the urinary tract that obstructs the flow of urine sets the stage for an infection. Waiting too long to pass urine; the use of catheters; or having diabetes, kidney stones, or an enlarged prostate gland can open the door to a urinary tract infection. Germs entering the urethra from sexual intercourse or improper wiping after a bowel movement may also cause a urinary tract infection.

Karl Kreder, M.D., UI Hospitals and Clinics urologist, says if you suffer from a urinary tract infection, you may notice:

• Increase in the frequency and urgency in trips to the restroom
• Increase in difficulty in starting the urine stream
• Heavy feeling or pain in the groin, bladder, or lower back area
• Urine that smells bad or looks milky, cloudy, or reddish in color
• Fever, nausea, or tiredness

You can do several things to help prevent a urinary tract infection, including:

• Urinate when you need to. Don’t wait.
• Drink water every day and after sex. Urinate after sex.
• Don’t use douches or feminine hygiene sprays.
• Wear underwear with a cotton crotch
• Drink cranberry juice

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