What Can Be Eaten Before a Colonoscopy?

Clear liquids are the only thing permitted while preparing for a colonscopy
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Preparing for a colonoscopy is the toughest part of getting a colonoscopy. That's because you'll have to cut out certain foods starting three days before the procedure. But knowing what you can eat will help the procedure go smoothly.


You'll eat a low-fiber diet starting a few days before your colonoscopy. The day before, you should ingest only clear liquids, like clear broth, bouillon, black coffee or tea, clear juice or frozen pops.

Preparing for a Colonoscopy

Colonoscopy preparation means following directions to empty the contents of your colon, explains Harvard Health Publishing. Your doctor should give you a colonoscopy prep plan, which will involve diet and bowel cleaning liquids. Following directions to the letter means you've cleaned your colon, and you'll have a smooth procedure.

Most colonoscopy preparation processes advise you to begin changing your diet three days before your procedure, according to Harvard Health Publishing. This means you should eat only low-fiber foods three days before. Kaiser Permanente has a handy chart in PDF form that you can print.

Think bland foods. White bread, white rice, plain crackers. Avoid whole grains and cereals with nuts and seeds. You can eat most meats three days before, but skip legumes. You can eat applesauce, ripe cantaloupe and honeydew, peeled apricots and peaches, and canned or cooked fruit without seeds or skin.

Eat only bland vegetables. Canned or cooked vegetables without skin or peel are best. You can eat peeled carrots, mushrooms, turnips, asparagus tips, potatoes without skin and peeled, seeded cucumbers. Avoid corn, tomatoes, cabbage and Brussels sprouts, peas, any type of squash and lima beans. Avoid nuts and seeds.

A Liquid Diet

The day before your colonoscopy, you'll consume a liquid diet, Harvard Health Publishing explains. This means that, for your colonoscopy diet, you can have chicken, beef or vegetable bouillon as long as it's a clear broth. You can have light-colored sports drinks, but many doctors do not want you to drink red or purple drinks.

You can also eat gelatin or fruit pops, but don't eat anything with red or purple. Also, make sure these foods don't contain chunks of fruit.

The day before, avoid any alcoholic beverages, smoothies, milkshakes, cream, grapefruit juice, tomato juice, cooked cereal and anything made with red or purple dye.

Read more: A Liquid Diet One Day Before a Colonoscopy

Why Clear Your Colon?

It's important that you follow these instructions. Your doctor wants to clearly see the insides of your colon to probe for any polyps, which are small growths. Polyps can grow into tumors, some of which could be cancerous.

Your doctor uses a colonoscope to look at the insides of your colon and rectum. This can show irritated or swollen tissue, ulcers, polyps or cancer, according to the National Institute of Diabetes and Digestive and Kidney Diseases.

A colonoscopy is important because, in America, cancers of the colon and rectum are the second leading cause of death among men and the third leading cause of death among women. A large, long-term study reported in the September 2013 issue of the New England Journal of Medicine found that 40 percent of colorectal cancers, or cancers of the colon and rectum, could have been prevented through colonoscopy screening.

Read more: 10 Foods Linked to Cancer You Need to Stop Eating Now

Steps to Better Colon Health

Eating a healthy diet can improve your colon health, according to Rush University Health & Wellness, which suggests:

  • Limiting red meat consumption and stay away from processed meats.
  • Lowering your sugar intake.
  • Increasing your fiber intake.
  • Getting enough calcium and vitamin D.
  • Choosing whole grains.

Still, make sure to follow your doctor's recommendations about getting regular colonoscopies. The American Cancer Society recommends getting your first screening at age 45 if you are at average risk and getting screenings every 10 years after that. If your doctor considers you to be at higher risk, check with her about how often you should get a colonoscopy.