The top 4 colonoscopy mistakes people make before their colorectal cancer screening

Don’t flunk your tush test.

Colorectal cancer is the fourth most common type of cancer in the US, with rates steadily on the rise — especially among people under 50.

While colonoscopies are considered the gold standard of screening, it’s essential to make sure you’re being anal about prep so you don’t get bum results.

Speaking to The Post, Dr. David Rivadeneira, a colon and rectal surgeon at Huntington Hospital and Director of the Northwell Health Cancer Institute at Huntington, revealed the top mistakes people make when it comes to their colonoscopies.

Mistake #1: Avoiding the probe altogether

The biggest mistake people can make is not getting a colonoscopy at all, whether because they don’t think they need it or because imagining a camera being put up their butts makes them uncomfortable.

“There’s a fear, right? There’s a fear of an invasive procedure,” said Dr. Rivadeneira, adding that some people get squeamish because of the part of the body, thinking,”They’re going up my rectum and looking with a camera.’”

But it’s truly the best thing you can do to catch it, so it’s important to get yours booked if you’re the right age.

Current guidelines advise patients to get their first colonoscopy at 45 — unless they’re at higher risk or have other predisposing factors, like a family history of colon cancer or polyps. In that case, discuss how soon you should be going with your primary care physician.

“People don’t realize exactly how significant that is. Family history is huge,” and particularly you have multiple family members, then there might be a genetic cause,” Dr. Rivadeneira said.

Mistake #2: Believing old stories about the clean-out process

The doc acknowledged that a lot of people are put off by the prep, which involves drinking a laxative formula to flush out your bowels — and means suffering through 12 to 16 hours of diarrhea.

“People are afraid of the prep more than anything. The clean out process, believe it or not,” he said. “I personally have had five colonoscopies. I never thought the cleanup process is that terrible, but a lot of people don’t want to drink a solution to give them diarrhea for several hours to flush out the colon. So a lot of people avoid the colonoscopy because of that reason alone.”

Your parents or older friends may have told you horror stories, but Dr. Rivadeneira promises the prep process has “improved significantly” over the past ten to 15 years.

“Before, it used to be four liters, a gallon of this awful tasting solution. It’s not like that anymore. There are smaller volume preps that work very well. There are pill preps that people can take. There’s a multitude of preps that are a little bit better than it used to be, but they all have the same effect.”

Mistake #3: Eating greasy foods

In addition to chugging a drink to make you go, go, go, it’s also important to follow the diet plan set out by your doctor — because if you don’t, there can be real consequences.

“We usually want people to kind of eat light, roughage type of diet for a couple of days before the procedure,” said Dr. Rivadeneira.

Sure, you’re also supposed to drink a laxative solution that’s meant to flush everything about — but it doesn’t work as well if you’ve been filling up on heavy foods.

“If you have several days of steak and potatoes … that stuff just kind of clings into your colon and just takes longer prep,” the doc explained.

“We want to catch these things early, so if it’s coated with stools and it’s not clean enough that we can see the inside lining of the colon, then we stop the procedure.”

A crappy view can also be dangerous: “If it’s dirty you can’t see properly, then you turn right when you’re supposed to turn left, and that’s when you get a perforation sometimes.”

Mistake #4: Not sticking to clear liquids for one to two days

Rivadeneira also stressed the importance of only drinking clear liquids for a day or two before your procedure for the same reason: Dark or milky ones can obscure the scope’s view.

“I usually do 24 hours of clear liquids, and that can be chicken broth, beef broth, vegetable broth, jello, Gatorade, ginger, anything clear,” he said.