an update of nutritional recommendations

Lhe prevalence of inflammatory bowel diseases (IBD), which includes Crohn’s disease, ulcerative colitis and indeterminate colitis, is, as various studies and reports point out, constantly increasing around the world. [1]a Europe [2] and in France [3]. These diseases, which are characterized by exacerbated inflammation in the intestinal wall, are generally caused by a dysfunction of the immune system [4]. Concerning the possible etiologies, it is accepted that they are multifactorial, and probably the result of genetic predispositions as well as complex epigenetic interactions intertwining genes and environment. With pharmacological treatments, nutritional support has its place in the therapeutic strategy. Hence the interest in the new recommendations published by theEuropean Society of Clinical Nutrition and Metabolism (ESPEN) which makes it possible to best guide clinical practice [5].

To develop these recommendations, the learned society called on numerous researchers as well as health professionals working in the context of IBD who worked together according to a well-codified procedure (cf. Boxed). The 70 recommendations were summarized and classified into different categories: prevention, screening and treatment of malnutrition, adoption of a specific diet, therapeutic nutrition and modulation of the microbiota.

Prevention: plants, omega-3 and breastfeeding

Recommendations for prevention most often come from retrospective case control studies. Therefore, the level of proof is limited.

However, it emerges that a diet rich in fruits, vegetables, and omega-3, and low in omega-6 is recommended, because it is associated with a reduced risk of IBD.

Recommendation grade: 0; agreement: 96 % (cf. Boxed).

Conversely, food consumption ultraprocessed (although this classification is still controversial) and food emulsifiers (like carboxymethylcellulose) could be associated with a increased risk of SMALL.

Recommendation grade: 0; agreement: 100 %.

Likewise, breastfeeding (for at least 6 months) is recommended, because it would play a protective role in the occurrence of IBD in children. Be careful, however, to avoid causing possible guilt in women who cannot or would not breastfeed.

Recommendation grade: B; agreement: 96 %.

Screen for and treat malnutrition

In people with IBD, the risk of malnutrition is increased especially in cases of Crohn’s disease and active disease. Malnutrition can be caused by insufficient nutrition (particularly because of its monotonous and restricted nature) or by malabsorption. Several recommendations make it possible to prevent and/or treat this condition:

• First, a initial screening at the time of diagnosis must be carried out and repeated regularly. Situations of malnutrition are associated with a worsening in terms of prognosis, complications, quality of life and mortality, and must be taken care of.

  Recommendation grade: GPP; agreement: 100 %.

  THE advice from a dietitian as part of multidisciplinary follow-uptaking into account the patient’s general lifestyle, are required.

  Recommendation grade: GPP; agreement: 100 %.

  Particular attention must be paid to people in obesity situation who present an increased risk of malnutrition and in whom the latter is less suspected. Obese people are advised to lose weight only when in stable remission.

  Recommendation grade: GPP; agreement: 100 %.

The deficiency in fer is one of the most common in people with IBD and must be corrected. It is also important to monitor the status in calcium/vitamin Despecially in patients receiving corticosteroid therapy to prevent bone demineralization.

Recommendation grade: B; agreement: 96 %.

No specific diet for IBD and preventive supplements in certain cases

Therapeutic diets are often on the rise in this type of pathology. Despite this, the recommendations suggest that there is no no specific diet having proven itself in the context of IBD: paleolithic, gluten-free, low in fermentable sugar (FODMAP), carrageenan-free, lactose-free, meat-free, rich in meat, vegetarian, enriched with omega-3… In particular, preventive supplements in omega-3 are not effective (Recommendation grade : A ; accord : 100 %).

It is advisable to follow the principles of a balanced diet and avoid foods that seem to cause problems.

Preventive prescription of vitamins is recommended in certain specific cases:

• an intestinal resection for vitamin B12 (Recommendation grade : B ; accord : 100 %) ;
• treatment with sulfasalazine and methotrexate for vitamin B9 (Grecommendation range: B; agreement 95%).

Therapeutic nutrition

Therapeutic nutrition represents all the techniques to support or replace, for a limited period, solid food. It includes oral supplementation, enteral nutrition via nasogastric tube, and parenteral nutrition directly via intravenous nutrition.

Oral supplementation is the first indicated due to its lack of invasiveness. If food intake is not sufficient, enteral nutrition can be considered and it is always preferable to parenteral nutrition, because it maintains the activity of the digestion process (recommendation grade : O ; accord : 96 %). It can represent the entire intake in children or adolescents with moderately active Crohn’s disease to initiate remission (recommendation grade : O ; accord : 96 %).

To avoid possible side effects, a nasogastric tube should be used as much as possible (recommendation grade : GPP ; accord 100 %). Concerning enteral nutrition formulas, standard solutions with moderate fat intake should be preferred to specific solutions with enrichments (recommendation grade : B ; accord 90 %).

Parenteral nutrition only intervenes as a last resort when oral nutrition and enteral nutrition are no longer sufficient to meet intake due to various complications (intestinal tract too short, obstruction of the intestinal tract, fistula, etc. [grade de recommandation : GPP ; accord : 100 %]).

Modulation of the microbiota: a promising avenue, but weak evidence

The microbiota is a potential new target in the treatment of IBD. However, for the moment, the data is not robust enough for this to be the subject of recommendations. Consequently, probiotics and prebiotics are not recommended in the context of Crohn’s disease, whether in the active phase of the disease or for prevention (recommendation grade : B ; agreement from 95 to 100 %).

Certain probiotics could be used very specifically in ulcerative colitis as an alternative to 5-aminosalicylic acid when this standard treatment is not tolerated (recommendation grade : O ; accord : 85 %).

Also, multi-strain probiotic compounds appear to be able to prevent pouchitis (idiopathic inflammation of the ileal reservoir after an ileo-anal anastomosis posttotal coloproctectomy) (recommendation grade O ; accord : 95 %).

Antibiotics are not recommended in the management of IBD and fecal transplantation is not indicated, given the vagueness surrounding its effectiveness (no arguments for or against) (agreement: 100%).

Physical activity too

Finally, the practicing physical activity Endurance training is recommended during the remission phase for all patients with IBD (and against resistance if muscle function is reduced).

Recommendation grade : GPP ; accord : 100 %.