Diet for Colonoscopy

Importance of Preparation

The diet is an integral part of the preparation for colonoscopy, regardless of whether it is the traditional optical exam or the virtual one.

• possible adjustment of pharmacological therapies in place and adoption of other prophylactic measures;
• low fiber diet ;
• use of drugs with laxative effect.

These measures are fundamental, because:

• allow the intestine to be cleaned well, which in turn is essential for the success of the exam (see figure to the side);
• involve less discomfort during colonoscopy;
• reduce the risk of complications.

Important Premises

1. If the patient does not follow the instructions provided by the medical center on the correct preparation for colonoscopy to the letter, the procedure may need to be repeated. In fact, if the intestinal walls are not sufficiently free from faecal residues, the doctor could decide to stop the investigation and postpone the colonoscopy.
2. In the preparation for colonoscopy some general rules can be defined MA:
   • every medical center to which one turns tends to adopt its own protocol, which in the final analysis is always "sewn on" to the patient if it is necessary to personalize some aspects, for example due to intolerances or allergies, diabetes, pregnancy, diseases intestinal inflammatory, use of certain drugs such as coumadin or clopidogrel, opportunities for antibiotic prophylaxis etc.
   • In the light of these considerations, the reader must always and in any case rely on the instructions provided by the medical center, even when they are in contrast with the concepts present in this article.

Colonoscopy diet

Diet is an integral part of any colonoscopy preparation process. The ultimate goal of this intervention is to thoroughly clean the walls of the intestine from fecal residues, which could remain despite taking the purgative:

• hiding small polyps or other formations
• making it difficult to observe the mucous membrane of the bowel
• increasing patient discomfort

Examples of diseases and conditions to be communicated to the medical center to obtain a protocol of preparation for a safe and personalized colonoscopy:

• diabetes
• glaucoma
• diverticula
• myocardial infarction in the last 6 months
• other cardiopathies (eg mitral valve prolapse, other valvulopathies etc.)
• presence of pacemakers or artificial heart valves
• allergies of any kind
• previous allergic reactions to certain drugs or anesthetics
• use of antiplatelet and anticoagulant drugs

To obtain a correct intestinal cleansing it is always recommended to take a purgative by mouth. In this regard, there are differences between the protocols adopted by the various endoscopic centers, which in the final analysis are always and in any case adapted to the individual patient (in the case of certain disorders or conditions, see table). It is therefore advisable to follow the instructions received with regard to the type of purgative to be used, the dosage schedule and the methods of recruitment.

The diet for colonoscopy is important because some eating habits can promote greater effectiveness of the laxative. Let's see some general rules:

• From 5/7 days before the exam:
  • suspend the intake of fruit and vegetables with seeds (such as grapes, kiwi, figs, strawberries, aubergines, tomatoes and the like);
  • suspend the intake of food supplements containing iron (which tends to color the intestinal walls black and has a constipating effect);
  • PLEASE NOTE: most of the centers restrict all these constraints to just 3 days before colonoscopy
• From 2/3 days before the exam
  • drink at least two liters of non-carbonated water per day (some centers recommend reaching 3 liters of water per day);
  • avoid large meals;
  • eliminate from the diet
    • all foods rich in slag (fibers), such as vegetables, legumes, fruit and fruit juices with pulp, whole grains (pasta, bread, biscuits, fiber-rich breakfast cereals, etc.), fatty meats and cheeses, chocolate, alcoholic beverages
    • avoid food rich in dyes (packaged foods with a particularly lively color)
    • avoid nuts and nuts in general, including foods that contain it (eg some cakes or sweets, peanut butter, muesli etc.)
    • avoid soups or jams containing traces of peel or seeds (eg strawberry jam and tomato jam);
  • the diet should therefore be based mainly on animal foods: eggs, lean meat, fish and broth, low-fat cheeses, homogenized with small amounts of white bread. Olive oil can be used as a condiment in small quantities. Yogurt is sometimes allowed, as long as it has no pieces of fruit; milk only if skimmed. Even potatoes can be eaten, as long as they are peeled.
  • Remember that above all there is always the main rule of avoiding large meals; the colonoscopy diet plans to limit the portions of food consumed in the 2/3 days prior to the exam.
  • Suspend the intake of charcoal, often present in some preparations against the problems of meteorism, flatulence and swollen belly, and other food supplements
• 1/2 days before the exam
• Fasting or semi-fasting is generally recommended (diet based on only liquid foods, chosen among those granted (avoiding corrections with milk and dairy products): water, tea, barley coffee, chamomile, sweetened and not sweetened with honey;
• It is necessary to follow the protocol concerning the correct intake of the purgative (eg polyethylene glycol, bisacodyl, saline and osmotive → isocolan etc.)
• Two hours before the exam
  • Completely suspend the intake of liquids.

PLEASE NOTE: in the case of a virtual colonoscopy many of the rules just mentioned apply, even if in general the diet is less restrictive. The risk, in this case, is that any faecal residues can be mistaken for polyps or other formations, increasing the risk of false positives.

If the subject suffers from chronic constipation, some studies overturn the rules just seen suggesting a diet rich in fiber (in order to improve intestinal transit and allow a complete colon cleansing).

Those just seen are just some general rules of the colonoscopy diet; remember that these indications vary slightly from one medical center to another. Therefore, in case of doubt, it is advisable to contact the medical center where the colonoscopy will be held.