Let's talk colonoscopies. To answer your probing questions, we turned to two specialists who say that yes, the nasty prep is worth the hassle.

What is a colonoscopy?

A screening test to prevent or find early cancers. One in five Minnesotans age 50 and older has at least one colon polyp, each of which has a 10 percent chance of turning into cancer. Taking polyps out can prevent up to 90 percent of colorectal cancer. The patient is sedated, then the doctor uses a flexible tube with a camera and light on it, called a colonoscope, to examine the rectum and inside the full length of the colon. If anything suspicious is found, the doctor can take a sample for biopsy.

Why is 50 the magical age for getting the first one?

Fifty is the starting age for people of average risk, taking into account the cost of screening and weighing risks vs. benefits. Studies show that age 50 best balances these factors. African-Americans and American Indians should start at age 45, due to higher risk.

What percentage of adults 50 and older actually get screened?

In Minnesota, 72 percent have had some kind of screening test. Nationally, about 50 percent.

What's the most common excuse for not getting one, and how do you respond?

People hear that the prep is unpleasant. They fear pain. Some fear that something might be found. In reality, most people tolerate the prep very well and sleep through the procedure.

How long do we have to wait for a better prep scenario, not that we don't love magnesium citrate?

There already are some improvements to make the liquids more palatable. The objective is to clean out the colon so you can see everything well. This takes volume. One new company has developed a machine that uses water to prep the colon, but that's not currently covered by insurance.

Why is consuming red liquids during the prep a no-no?

Polyps can be rather flat and have a pink hue. Red liquids can hinder the ability to see these polyps.

Do all doctors require the same prep?

No. Different clinics use different preps. We chose our sports drink prep because it worked, patients like it, and are more likely to finish it, and it does not require a prescription. Certain medical problems, such as renal dysfunction, require different preps.

What happens if I'm not fully cleaned out before the procedure?

Small amounts of stool can be removed with the colonoscope. At the end of the prep, what should be going in the toilet should look like lemonade. If it isn't, the patient should call for instructions.

How long does the procedure take? Are there any risks?

Twenty to 30 minutes. Risks such as perforation of the colon, or bleeding after the removal of polyps, are rare.

What's the oddest thing you've discovered within someone's colon?

Earrings, Monopoly pieces. A tapeworm.

How much does a colonoscopy cost? Are colonoscopies covered by most insurance carriers?

The cost varies widely, from zero to $3,000 or more, based on many factors. The Affordable Care Act mandated that screening colonoscopies be covered by commercial and government payers. Patients should review their health insurance plan for specific details.

What's the best thing we can do to decrease our chance of developing colon cancer?

Get screened when you are due. Don't smoke. Eat a healthy diet high in fruits and vegetables and low in animal fats, especially highly processed meats. Regular moderate exercise and maintaining a healthy weight also reduce the risk.

Do you ever wish you'd chosen dermatology?

Treat rashes and pus? Give me poop any day.

answers provided by Dr. David Perdue, M.D., MSPH, and Dr. Doug Nelson, M.D., with Minnesota Gastro­enterology, P.A.