Everyone hates colonoscopies—but they’re not as bad as they used to be
From AI to heartier diets, the dreaded procedure has gotten some recent upgrades that should make them less agonizing for patients.
Having a doctor stick a camera up your butt searching for cells that could turn into cancer is never going to be fun. But it’s still the most effective way to screen for colon and rectal cancer, the second deadliest type of cancer in the United States. Regular colonoscopies reduce colorectal cancer incidence by up to 41 percent and slash deaths from the disease in half, according to a study this spring that tracked tens of thousands of Europeans.
Even so, nearly 30 percent of Americans eschew the colorectal cancer screens they’re eligible for, including colonoscopies. Some mistakenly think they’re not at risk because they don’t have a family history or physical symptoms—although most cases of colon cancer have neither.
Others avoid colonoscopies, because they perceive the preparation to be onerous, says Aasma Shaukat, a gastroenterologist and researcher at New York University’s Grossman School of Medicine. “More than the procedure itself, the preparations the day before are the biggest cited barriers to signing up,” she says.
Fortunately, your next colonoscopy should be a lot better. A task force convened by three gastroenterology groups released new medical guidelines for colonoscopy prep this year, updating advice from 2014. The recommendations provide for less restrictive pre-procedure diets and cleanses, which, combined with other advances in the screenings, may sway some of the holdouts.
The new guidance will help older people as well as those 45 to 50, who have seen an increase in screening—and in colon cancer rates. The recommended start age for routine screening dropped from 50 to 45 in 2021, and patients typically get tested ever 10 years. (Still, only a third of people in their forties have had the procedure.) People with inflammatory bowel disease, a family history of early-onset colorectal cancer, or other factors might start earlier.
(Colon cancer is rising in young people. Finally, scientists have a clue about why.)
According to the American Cancer Society, doctors will diagnose more than 150,000 colorectal cancers this year, and the disease will cause some 50,000 deaths.
Colonoscopies or other colon cancer screening techniques will never be eagerly anticipated, but there are reasons to feel less dread the next time you’re due. Here are five important improvements.
1. No more starving beforehand
A thorough clean-out of the colon is crucial for a successful colonoscopy to enable doctors to examine its entire interior surface. Currently, just two-thirds of patients come to their procedures sufficiently cleansed. The first step is a special diet beforehand that left people hungry, hangry, and often unable to work productively.
“A lot of dietary recommendations used to be fairly draconian, but the evidence that accumulated over the last five years shows they need not be,” says Shaukat, a member of the task force.
Say good-bye to the water, gelatin, and broth clear-liquid diet previously recommended for the day before a colonoscopy. Studies have shown that eating low-fiber foods instead for much of the day successfully cleans the bowel. Some studies even found the food-based diet is superior.
The new guidance lets people choose more expansive options for breakfast and lunch. Eggs, yogurt, ham, and/or a bagel with cream cheese are now permissible for breakfast, while chicken and white rice or macaroni and cheese can be eaten for lunch. “You can feel pretty full eating this way,” Shaukat says.
Even dinner has gotten an upgrade. Liquids are still required for this meal, but this can be a thicker soup like butternut squash or potato rather than thin broth, or a smoothie made without fruits.
Everyone must avoid high-fiber foods such as fruits, vegetables, and whole grains the day before a colonoscopy—but not three days before, as some GI doctors previously instructed.
2. Gallon-jug preps are a thing of the past
The next step in the cleaning process is also getting easier. Formulations of bowel purgatives that required drinking a gallon of (often horrible tasting) liquid are giving way to preps comprised of a quarter of this volume. Some newer brands are tablets, taken with tap water.
The timing for the medication has also improved for most people. Instead of consuming everything the night before a colonoscopy, the guidance recommends taking half the dose that evening and the remainder four to six hours prior to the scheduled procedure.
The older requirements kept people up all night, since they had to spend so much time in the bathroom, Shaukat says. What’s more, taking part of the purgative the day of a procedure actually leads to better cleansing, research shows. People with afternoon procedures may be able to consume both doses on the day.
3. AI can help pinpoint polyps
Artificial intelligence is adding a second set of eyes to the gastroenterologists as the colonoscopy scope snakes through the intestines. One AI-assisted device approved by the U.S. Food and Drug Administration in 2021 paints boxes around areas assumed to be polyps, directing the gastroenterologist to examine the area.
The device increases detection of polyps by 20 percent. Still, research has not yet proven it reduces the risk of colon cancer itself. And doctors may get so used to the AI help some lose their ability to spot polyps without it, a study published in the Lancet in August found.
Major medical societies are not currently recommending AI’s widespread adoption; for now, it’s primarily major medical centers like Yale Medicine and the University of Colorado Hospital that are using it.
4. More pain-relief options help avoid sedation
Most people in the U.S. undergo colonoscopies while sedated, although a small number experience the procedure without the drugs. Some want to avoid potential, if rare, respiratory complications; others may wish to drive themselves home and not be groggy after.
Many people can get through the procedure without sedation. When doctors offered patients the option to receive a sedative if they decide they need it, nearly all completed the procedure without. Still, physicians sometimes underestimate the level of discomfort patients experience.
One alternative to lessen the pain is to employ transcutaneous electrical nerve stimulation, or TENS, on the wrist and ankle. Researchers in China recently found this sufficiently lowered pain in colonoscopies without sedation.
The mild electrical impulses are believed to stimulate nerves that mask pain signals as they also release pain-relieving endorphins. “TENS activates receptors as a part of your body's natural pain fighting system; thus, you do not have the associated side effects that can occur with opioid medications,” says Carol Vance, a physical therapist and researcher at Iowa’s Carver College of Medicine, whose review of the method found TENS may be effective for a variety of other pain conditions.
While Vance isn’t sure she’d opt for a colonoscopy without sedation herself, she notes the rigorous study does support its use in this way.
Another option on the horizon is virtual reality. Shaukat is halfway through a study where patients don VR goggles during their procedure (with sedation on standby), based on studies finding the method lessens other types of pain. “So far, patients have really liked the experience,” she says.
(How you think about physical pain can make it worse.)
5. Non-colonoscopy options are expanding
Last summer, the FDA approved a test that checks for colon cancer in the blood, called Shield. After blood is drawn, a laboratory searches for proteins and DNA fragments that are associated with the disease. Shield correctly identified 83 percent of people with colorectal cancer in a study published last year.
(Read more about the first FDA-approved blood test for colon cancer.)
The test joins the ranks of stool tests that have been offered for years, including fecal immunochemical tests (FIT) that detect blood in the stool, done annually, or those assessing atypical DNA that may indicate polyps or cancer, repeated every three years. All these tests require follow-up colonoscopies if results are positive.
Other options include flexible sigmoidoscopies—scopes that check only the lower-third of the colon—or virtual colonoscopies where x-rays and computers evaluate the GI tract, each repeated every five years.
In the future, sticking the camera up from the bottom might become a thing of the past, as capsule endoscopies could become a mainstream screen. (It’s currently approved for very limited indications.) Patients swallow a camera the size of a big pill that sends pictures it takes as it winds its way through the colon to the doctor’s computer, before exiting the other end.
Over the years, people are able to switch from one approved test method to another. Some younger patients who aren’t psychologically ready for a colonoscopy, for example, may do a stool-based test for several years, and would need the scope only if results are positive.
As Shaukat regularly tells her patients, “The best test is the one that gets done.”
