Diet guide for colonoscopy prep
Easy-to-read guides for each phase of your preparation diet. Choose the section that matches where you are in your prep.
When to follow this phase
Typically 4 days before your colonoscopy
A low-fibre diet reduces the amount of undigested material in your colon, making the final prep solution more effective. Choose foods that are soft, refined, and easy to digest.
Gluten challenge for Coeliac testing
Your doctor is taking biopsies to check for Coeliac disease. For the test to be accurate, you need to keep eating gluten before the procedure.
- Continue eating normal amounts of wheat, barley, rye, and oats (if you usually eat them).
- If you are already on a gluten-free diet, speak with your doctor about a formal gluten challenge before the test. A common challenge is the equivalent of 2 slices of wheat bread daily for about 6 weeks.
- Do not start a gluten-free diet until after your procedure and your doctor has discussed the results with you.
- The low-fibre and clear-liquid diet instructions still apply, but choose gluten-containing refined options where possible (e.g., white bread, plain wheat biscuits, white pasta) until your prep phase begins.
If you have already cut out gluten, let the clinic know before your appointment. Your doctor may need to reschedule the biopsies or adjust the advice.
Extended prep — if you are prone to constipation
Starting 4 days before your colonoscopy
- Take 1–2 sachets of Movicol or OsmoLax twice daily (morning and evening) for three days.
- Cease the Movicol or OsmoLax before you start the Picoprep (or similar) preparation.
Foods you can eat
These foods are generally low in fibre and gentle on the digestive system.
Grains & starches
- White bread, rolls, and crackers
- Plain white rice and pasta
- Pancakes or waffles made with white flour
- Potatoes without skin
Proteins
- Eggs prepared any style
- Chicken, turkey, and fish
- Tofu
- Smooth nut butters in small amounts
Fruits & vegetables
- Ripe bananas, melons, and peeled apples
- Cooked vegetables without skin or seeds
- Strained fruit juices without pulp
- Small amounts of applesauce
Dairy & extras
- Cheese, milk, and yoghurt in moderation
- Butter, margarine, and oils
- Plain cakes, biscuits, and pastries
- Clear broths and soups
Foods to avoid
These foods leave more residue in the colon and can make the prep less effective.
- Whole grains, brown rice, and bran cereals
- Raw vegetables, salads, and corn
- Nuts, seeds, popcorn, and chunky nut butters
- Legumes such as beans, lentils, and chickpeas
- Dried fruits, berries, and fruits with seeds or skins
- Tough or fibrous meats
Sample low-fibre day
Breakfast
Scrambled eggs, white toast with butter, ripe banana
Lunch
Chicken breast, white rice, cooked peeled carrots
Dinner
Baked fish, mashed potatoes, clear broth
Important reminder
This is a general guide. Your doctor may have specific restrictions, especially if you take blood thinners, diabetes medications, or have other health conditions. Always confirm your diet plan with your care team.