Low-residue diet before colonoscopy

Low-residue diet before colonoscopy: day-by-day guide

The low-residue diet before a colonoscopy clears the bowel of seeds, fibres and residue so the laxative works as it should and the doctor gets a clear view of the lining. Follow it properly and you reduce both discomfort during the bowel prep and the risk of having to repeat the examination because the bowel was not clean enough.

This is the practical day-by-day plan we hand out at Kirurgen.dk in Charlottenlund.

Why a low-residue diet at all?

Whole seeds, nuts and insoluble fibre can lodge in the folds of the bowel or block the working channels of the scope. Even a small amount of fibrous stool can cover small polyps. The diet is not a health regimen but a short preparation that makes the procedure safe and diagnostically accurate.

3 days before the colonoscopy

Switch gradually to easily digested food. You can still eat real meals, but avoid:

• wholegrain or seeded bread, muesli, rolled oats
• nuts, almonds, any seeds (sesame, linseed, chia, sunflower)
• coarsely grated raw fruit and vegetables with skin or seeds
• pulses (beans, lentils, chickpeas)
• popcorn, seeded crackers

You can eat:

• white bread, light rolls, plain crackers
• pasta, rice, peeled boiled potatoes
• lean meat, fish, eggs, soft cheese
• peeled, cooked or baked vegetables (carrot, courgette, potato)
• peeled apple, banana, stewed fruit, jam without seeds

2 days before: softer food and more fluid

Same principles, but start tapering solid food. Eat small frequent meals and drink 2–3 litres of water, clear juice or squash through the day. This trains the gut for the volume of fluid you will drink during the bowel prep.

The day before: clear fluids only

By noon at the latest, have your last small solid meal (for example a white roll with butter, or a piece of plain boiled chicken). After that you may only have clear fluids until the procedure. "Clear" means you can see through it.

Allowed:

• water, sparkling water
• clear squash, apple juice without pulp, light cola, lemon water
• clear broth (chicken, vegetable), clear soup with no solids
• tea and coffee without milk
• ice lollies and sorbet without berries or fruit pieces

Not allowed:

• milk, cream, yoghurt, drinkable yogurt
• orange juice with pulp
• tomato or vegetable juice
• red, blue or purple drinks (red wine, blueberry juice, beetroot juice). The colour can look like blood in the bowel.
• creamed soups and broth cubes with visible solids

The first sachet of laxative is usually taken in the afternoon, the second in the evening. You will receive a precise timetable for your specific product (most often Picoprep or MoviPrep).

Day of the procedure

You may drink clear fluids up to 2 hours before the colonoscopy. This reduces both thirst and headache. If you take regular medication, follow the separate instructions you were given: most tablets can be swallowed with a small sip of water, while blood thinners must be paused by agreement.

A practical overview

When	Food	Note
3 days before	Low-residue, no seeds or fibre	Regular meals, just seed- and fibre-free
2 days before	Softer food, more fluid	Gradual taper
Day before, until noon	Last small solid meal	Light roll, boiled chicken or similar
Day before, from noon	Clear fluids only	Water, apple juice, broth, tea without milk
Day before, afternoon and evening	Bowel prep + clear fluids	Follow the medication schedule exactly
Day of the procedure	Clear fluids up to 2 hours before	Then stop drinking completely

Frequently asked questions

Can I drink coffee? Yes, black coffee without milk is allowed up to 2 hours before the procedure. Milk or cream makes it cloudy and is not recommended.

What if I am hungry? Drink a sweet clear fluid such as apple juice or squash. The sugar gives energy and keeps nausea down.

Can I chew gum? Yes, sugar-free gum is fine and can ease hunger and thirst.

I have diabetes — what do I do? We take this into account in the individual plan. Call the clinic and we will agree on insulin and food before, during and after the bowel prep.

Ready for the procedure?

Read the full colonoscopy patient guide for what happens on the day of the examination, which side effects may occur, and how you get home afterwards.