
Preparing for a colonoscopy can be a hassle. Your colon has to be as empty as possible so that your doctor can look for polyps and other signs of cancer. So while it’s an exam most people dread, it’s worth the effort involved.
Before a colonoscopy, you should avoid solid foods for at least 24 hours and stick to a clear liquid diet for breakfast, lunch and dinner. Ask your doctor about what you can have and when, since in some cases you may be allowed to eat easily digestible foods up to 14-16 hours before the procedure if you aren’t able to fast for long.
What should you avoid having before a colonoscopy?
Following a clear liquid diet means you should avoid eating any solid foods, including:
- Bread, grains, rice or cereals
- Soups with chunks of food
- Meat
- Milk or dairy products
- Vegetables
- Fruits
Liquids to avoid include:
Clear liquids you can have include:
- Water, including mineral water
- Soda
- Club soda
- Black coffee with no cream or milk
- Sports drinks with electrolytes
- Apple juice
- Tea without milk
- Honey
- Flavored gelatin
- Clear broth
What’s involved in preparing for a colonoscopy?
Plan ahead
Your doctor will give you instructions when scheduling your colonoscopy. Make sure to read them carefully and talk to your doctor if you have any questions.
Stock up on these items before the procedure:
- Low-fiber foods
- Sports drinks, juices and broths
- Wet wipes
- Diaper cream
- A prescription or over-the-counter laxative specified by your doctor
Change your diet
Eating light foods 3-4 days before the procedure can help ease the colon-cleansing process. Low-fiber foods are generally recommended because they are easy to digest.
You can eat:
- White bread, pasta and rice
- Well-cooked vegetables without skin
- Fruit without skin or seeds
- Lean meat, chicken or fish
- Eggs
Do not eat:
- Seeds, nuts or popcorn
- Fatty foods
- Tough meat
- Whole grains
- Raw vegetables
- Fruit with seeds or peel
- Corn, broccoli, cabbage, beans or peas
Stop taking vitamins or other supplements at this point. If you are taking blood-thinning or other over-the-counter anti-inflammatory medicines, make sure to ask your doctor about whether you should stop.
Fast for 24 hours
As discussed above, you should stop eating solid foods a full day before the procedure. Stick to only clear liquids.
Take laxatives
The night before your colonoscopy, you will need to take strong liquid laxatives, usually a half gallon, to clear your digestive tract. Six hours before the procedure, you will need to take another half-gallon of liquid laxative.
Since laxative solutions often have an unpleasant taste, you may want to mix yours with a flavored sports drink or powdered drink mix.
Once the laxatives start working, you will experience frequent, forceful diarrhea. You may also experience:
Stay calm
The purging process can be rough. Here are a few tips to make yourself as comfortable as you can:
- Stay in the bathroom and entertain yourself by reading a book or listening to music.
- Apply diaper cream before diarrhea starts.
- Use medicated wet wipes to clean yourself.
Once your bowels have been cleansed, your stool will look like urine or clear water. This means you’ve completed the process and your colon is ready for the colonoscopy.
While it’s not easy, remember that the better you prepare, the faster the procedure will be, and you may not have to do it again for another 10 years.

QUESTION
What are risk factors for developing colon cancer? See AnswerUCLA Health System. Preparing for Your Colonoscopy. https://www.uclahealth.org/Workfiles/brochures-programs/preparing-colonoscopy-en.pdf
Top Can I Eat 24 Hours Before a Colonoscopy? Related Articles
Colon Cancer (Colorectal Cancer)
Colon Cancer (Colorectal Cancer) is a malignancy that arises from the inner lining of the colon. Most, if not all, of these cancers, develop from colonic polyps. Removal of these precancerous polyps can prevent colon cancer.Colon Cancer: How Your Food and Diet Can Affect Colorectal Cancer Health
Diet, including nutrient, antioxidant, and vitamin intake, affects colon cancer risk. Certain dietary factors either decrease or increase the risk of colorectal cancer, breast cancer, and other diseases. Dietary factors may either inhibit or stimulate the development of cancer cells. Have a nutrition plan that decreases the risk.Colon Cancer Illustrations
Most, if not all, of these cancers develop from colonic polyps. Removal of these precancerous polyps can prevent colon cancer. See a picture of Colon Cancer and learn more about the health topic.Colon and Colorectal Cancer Screening
Colon cancer is preventable by removing precancerous colon polyps, and it is curable if early cancer is surgically removed before cancer spreads to other parts of the body. Therefore, if screening and surveillance programs were practiced universally, there would be a major reduction in the incidence and mortality of colorectal cancer.Colonoscopy Procedure and Preparation
A colonoscopy is a procedure whereby a docotor inserts a viewing tube (colonoscope) into the rectum for the purpose of inspecting the colon. Colonoscopy is the best method currently available to diagnose, detect, and treat abnormalities within the colon.Colon Cancer Slideshow
Colorectal cancer (colon cancer) is the cause of many cancer deaths. Learn about the warning signs, symptoms, screening process, stages, and treatment related to colorectal cancer.Early Signs of Colon Cancer
Colon or colorectal cancer may not cause any symptoms during the early stages of the disease. A person may have polyps or colon cancer but may not have any symptoms till the late stages of the disease.Colon Cancer: 8 Early Warning Signs & 4 Stages
Colon cancer usually does not cause signs or symptoms in the early stages. As the cancer grows, signs may include blood in the stool, bowel habit changes, abdominal pain, and fatigue. Learn about stages and treatment of colon cancer.Can I Eat Mashed Potatoes 2 Days Before Colonoscopy?
Colonoscopy is a procedure used to detect abnormalities in the large intestine (colon). One day before the procedure, it is advised not to eat any solid or semi-solid food, such as mashed potatoes, applesauce, oatmeal, etc. A clear liquid diet must be taken 24 to 72 hours before the procedure.Endoscopy vs. Colonoscopy
Both endoscopy and colonoscopy are nonsurgical procedures that involve use of a flexible tube with a light and camera to examine parts of the digestive tract. A colonoscopy is a type of endoscopy.How Long Before a Colonoscopy Should I Stop Drinking Water?
A colonoscopy is a test to look at the inside of the colon. Usually, doctors recommend patients undergoing a colonoscopy to stop drinking clear liquid or water at least three to four hours before the procedure. However, patients with diabetes and who are dehydrated may take a few sips of water after consulting their doctor.Sigmoidoscopy vs. Colonoscopy
Both sigmoidoscopy and colonoscopy are nonsurgical procedures that involve use of a tube (endoscope) with a light and camera to examine parts of the large intestine (colon). A sigmoidoscopy is a procedure in which a fiberoptic camera is used to examine the rectum and lower part of the colon. The difference between a sigmoidoscopy and colonoscopy is that a colonoscopy examines the upper part of the colon as well.Virtual Colonoscopy
Virtual colonoscopy is a procedure that uses a CT scan to construct virtual images of the colon. Virtual colonoscopy takes approximately 10 minutes, and in comparison to traditional colonoscopy is less invasive and requires no conscious sedation. Virtual colonoscopy may not be recommended for some patients due to their medical history.