What Can I Eat the Day Before a Colonoscopy?
What Can I Eat the Day Before a Colonoscopy?
Ever since the dawn of colonoscopy, nearly all patients have been advised to go on a clear liquid diet the day before a procedure and to avoid any solid foods. But new multi-society guidance suggests another way.
We highlighted this idea several years ago when Dr. Jeff Scott from Happy Colon Foods presented a way for colonoscopy prep to “not suck,” where he showed studies indicating a low-residue diet would not only make “prep day” more comfortable, but it would result in a sufficient colon cleanse. After undergoing a thorough review, the U.S. Multi-Society Task Force on Colorectal Cancer updated their official recommendations for bowel prep prior to a colonoscopy. These were published in the March 5, 2025 issue of Gastroenterology.
When it comes to what you can eat the day before a colonoscopy, the updated recommendations state:
“We recommend limiting dietary restrictions to the day before a colonoscopy, relying on either clear liquids or low-fiber/low-residue diets for the early and midday meals.”
This is a major change for patients who struggle to fast and follow the clear liquid diet the day before a colonoscopy.
“We know that a huge barrier to completing colonoscopy is the prep,” said Swati G. Patel MD, MS, CGAF. “If we can make the process just a tad easier, it can go a long way towards improving screening rates.”
Clear liquid diet for colonoscopy prep
The updated recommendations do not eliminate the suggestion of following a clear liquid diet prior to a colonoscopy. The following would fall under this category:
And for those who are wondering if Diet Coke counts as a clear liquid, the answer is YES!
Low fiber diet for colonoscopy prep
But now, you may be able to eat a low-fiber breakfast and lunch the day before your colonoscopy. It will be important to err on the safe side. If you have any questions about if a food is low fiber or not, ask your doctor or avoid eating it, and choose an option you’re certain is on the list.
What foods are part of a low fiber diet? Anything with whole grains, nuts, seeds, and skins are NOT low fiber. Generally, canned or cooked foods are allowed, but not raw or dried fruits or veggies.
Here’s a quick list of what you could safely eat for breakfast and lunch (before 2pm) on the day before a colonoscopy:
How does a low fiber diet help with colonoscopy prep?
Some people have a hard time fasting the day before a colonoscopy, and a low-fiber diet may help curb hunger and make prep night more tolerable.
Research shows that when comparing patients who followed a clear liquid diet to those who ate a low fiber diet on the day before a colonoscopy, both patient groups had sufficient preps that meant the doctors could perform the colonoscopy.
However: It was critical for the patients to follow all prep instructions, and to take all the prep product.
“Our goal is to prescribe a prep that is the least painful for our patients, but still achieves a high-quality cleanse so we can get a good look,” Dr. Patel said. “We often have to customize the prep for patients. It is important to share your full medical history and medication list with your colonoscopy doctor’s office. There are certain medical conditions and medications that slow down the bowels. In these scenarios, eating solids prior to your procedure may not be a good idea and you may even need a more aggressive prep. Based on your specific situation, the doctor’s office will recommend a prep that is compatible with your medical issues and has the highest chance of producing a good quality prep. In the end, the most important thing is to follow the instructions to minimize the risk of missing a polyp, or having to repeat the colonoscopy due to suboptimal prep.”
Colonoscopy diet is very important
A colonoscopy prep diet is very important, as it’s part of what makes a colonoscopy lifesaving. While this guidance does ease up on the clear liquid diet the day before a colonoscopy, it’s important to work closely with your doctor and eat mindfully and cautiously. When in doubt, stick to clear liquids so your colon will be as clean as possible.
Why?
A cleansed colon will give your gastroenterologist a good look, ensuring nothing is missed. It will also help you avoid an incomplete prep, which leads to needing to redo prep night, reschedule your procedure, and possibly pay more.
Ever since the dawn of colonoscopy, nearly all patients have been advised to go on a clear liquid diet the day before a procedure and to avoid any solid foods. But new multi-society guidance suggests another way.
We highlighted this idea several years ago when Dr. Jeff Scott from Happy Colon Foods presented a way for colonoscopy prep to “not suck,” where he showed studies indicating a low-residue diet would not only make “prep day” more comfortable, but it would result in a sufficient colon cleanse. After undergoing a thorough review, the U.S. Multi-Society Task Force on Colorectal Cancer updated their official recommendations for bowel prep prior to a colonoscopy. These were published in the March 5, 2025 issue of Gastroenterology.
When it comes to what you can eat the day before a colonoscopy, the updated recommendations state:
“We recommend limiting dietary restrictions to the day before a colonoscopy, relying on either clear liquids or low-fiber/low-residue diets for the early and midday meals.”
This is a major change for patients who struggle to fast and follow the clear liquid diet the day before a colonoscopy.
“We know that a huge barrier to completing colonoscopy is the prep,” said Swati G. Patel MD, MS, CGAF. “If we can make the process just a tad easier, it can go a long way towards improving screening rates.”
Clear liquid diet for colonoscopy prep
The updated recommendations do not eliminate the suggestion of following a clear liquid diet prior to a colonoscopy. The following would fall under this category:
And for those who are wondering if Diet Coke counts as a clear liquid, the answer is YES!
Low fiber diet for colonoscopy prep
But now, you may be able to eat a low-fiber breakfast and lunch the day before your colonoscopy. It will be important to err on the safe side. If you have any questions about if a food is low fiber or not, ask your doctor or avoid eating it, and choose an option you’re certain is on the list.
What foods are part of a low fiber diet? Anything with whole grains, nuts, seeds, and skins are NOT low fiber. Generally, canned or cooked foods are allowed, but not raw or dried fruits or veggies.
Here’s a quick list of what you could safely eat for breakfast and lunch (before 2pm) on the day before a colonoscopy:
How does a low fiber diet help with colonoscopy prep?
Some people have a hard time fasting the day before a colonoscopy, and a low-fiber diet may help curb hunger and make prep night more tolerable.
Research shows that when comparing patients who followed a clear liquid diet to those who ate a low fiber diet on the day before a colonoscopy, both patient groups had sufficient preps that meant the doctors could perform the colonoscopy.
However: It was critical for the patients to follow all prep instructions, and to take all the prep product.
“Our goal is to prescribe a prep that is the least painful for our patients, but still achieves a high-quality cleanse so we can get a good look,” Dr. Patel said. “We often have to customize the prep for patients. It is important to share your full medical history and medication list with your colonoscopy doctor’s office. There are certain medical conditions and medications that slow down the bowels. In these scenarios, eating solids prior to your procedure may not be a good idea and you may even need a more aggressive prep. Based on your specific situation, the doctor’s office will recommend a prep that is compatible with your medical issues and has the highest chance of producing a good quality prep. In the end, the most important thing is to follow the instructions to minimize the risk of missing a polyp, or having to repeat the colonoscopy due to suboptimal prep.”
Colonoscopy diet is very important
A colonoscopy prep diet is very important, as it’s part of what makes a colonoscopy lifesaving. While this guidance does ease up on the clear liquid diet the day before a colonoscopy, it’s important to work closely with your doctor and eat mindfully and cautiously. When in doubt, stick to clear liquids so your colon will be as clean as possible.
Why?
A cleansed colon will give your gastroenterologist a good look, ensuring nothing is missed. It will also help you avoid an incomplete prep, which leads to needing to redo prep night, reschedule your procedure, and possibly pay more.
