Nutrition in inflammatory bowel disease (IBD)


Inflammatory bowel disease (IBD) is a chronic condition that affects millions of people worldwide. Inflammatory bowel disease (IBD) is characterized by inflammation of the digestive tract, which can lead to a variety of symptoms including abdominal pain, diarrhea, and fatigue. While there is no known cure for IBD, managing the condition through diet and lifestyle changes can greatly improve quality of life for those living with it.

In this article, we will explore the role of nutrition in managing IBD and highlight some key dietary recommendations for those looking to improve their symptoms and overall health, based on the current (2023) ESPEN guideline on clinical nutrition in inflammatory bowel disease (IBD).

Are there any specific dietetic recommendations, suggesting that diet promotes or protects against inflammatory bowel disease (IBD)?

Consuming a diet abundant in fruits and vegetables, high in n-3 fatty acids, and low in n-6 fatty acids has been linked to a lower risk of developing IBD, making it a recommended approach. On the other hand, there is a potential association between ultra-processed foods, dietary emulsifiers like carboxymethylcellulose, and an elevated risk of developing IBD. As a result, it may be advisable to avoid them in general.

Furthermore, encouraging breastfeeding is crucial as it provides infants with the best possible nutrition and decreases their likelihood of developing IBD.

What are the risks and consequences of malnutrition in inflammatory bowel disease (IBD)?

Due to the increased risk of malnutrition in patients with IBD, it is recommended to screen for malnutrition at the time of diagnosis and periodically thereafter. In cases where malnutrition is documented in individuals with IBD, prompt and appropriate treatment is crucial as it can worsen the prognosis, increase complication rates, mortality, and negatively impact quality of life.

Do patients with inflammatory bowel disease (IBD) have different energy requirements compared to the general population?

As a general guideline, individuals with IBD should receive an energy delivery of 30-35 kcal/kg/day, which is comparable to the energy needs of the general population. However, in cases where specific disease states are suspected to affect energy requirements, determining individual energy needs through indirect calorimetry and considering their physical activity level is recommended.

Do patients with inflammatory bowel disease (IBD) have different protein requirements compared to the general population?

During active IBD, protein requirements tend to increase, and individuals should consume higher amounts of protein (1.2-1.5 g/kg/d in adults) compared to the general population. However, during remission, protein requirements are typically not elevated, and individuals should consume a similar amount of protein (around 1 g/kg/d in adults) as recommended for the general population.

Do patients with inflammatory bowel disease (IBD) have different micronutrient requirements compared to the general population?

Regular screening for micronutrient deficiencies is important for individuals with IBD, including during the remission phase, and any identified deficiencies should be addressed promptly and appropriately.

Is iron supplementation necessary in inflammatory bowel disease (IBD)?

For patients with iron deficiency or mild anemia and clinically inactive disease who have not had previous intolerance to oral iron, oral iron supplementation should be the primary treatment option. In contrast, intravenous iron supplementation should be considered the first-line treatment for patients with:

  • clinically active IBD
  • previous intolerance to oral iron
  • hemoglobin levels below 10 g/dL
  • or those requiring erythropoiesis-stimulating agents.

You can estimate the total iron requirements as shown in the Table below.

Hemoglobin, g/dLBody weight <70 kgBody weight ≥70 kg
10-12 (women)1000 mg1500 mg
10-13 (men)1000 mg1500 mg
7–101500 mg2000 mg

Following effective treatment of iron deficiency anemia with intravenous iron, subsequent treatment with intravenous iron should begin promptly upon the serum ferritin level dropping below 100 μg/L (or ng/mL) OR hemoglobin levels falling below 12 or 13 g/dL depending on the individual’s gender.

What is the role of dietitians and nurses for patients with inflammatory bowel disease (IBD)?

As part of the multidisciplinary approach to enhance nutritional therapy and prevent malnutrition and nutrition-related complications, it is recommended that all patients with IBD receive individualized counseling from a dietitian. Nurses are an essential component of the multidisciplinary IBD team, and their roles should encompass nutritional screening and dietary management contributions.

Should patients with inflammatory bowel disease (IBD) with active disease adhere to a specific diet?

There is currently no universally recommended “IBD diet” to induce remission in individuals with active IBD.

For pediatric patients with mild to moderate Crohn’s disease (CD), a CD exclusion diet in combination with partial enteral nutrition (EN) may be considered as an alternative to exclusive EN to achieve remission.

For adult patients with mild to moderate active Crohn’s disease (CD), a CD exclusion diet with or without enteral nutrition can also be considered.

Are there subgroups of patients with Crohn’s disease (CD) with particular nutritional needs?

Due to the possibility of malabsorption or maldigestion in individuals with Crohn’s disease (CD), dietary counseling should take this into consideration.

For patients with CD who experience intestinal strictures or stenosis along with obstructive symptoms, a diet with modified texture or exclusive enteral nutrition (EN) delivered through a tube positioned beyond the obstruction (post-stenosis) may be recommended.

Individuals, both adults and children, diagnosed with IBD and experiencing active disease, currently being treated with corticosteroids, or suspected of having hypovitaminosis D, should undergo regular monitoring of their serum 25(OH) vitamin D levels. If deemed necessary, calcium and vitamin D supplements should be prescribed to prevent low bone mineral density. In cases of osteopenia and osteoporosis, treatment should adhere to the latest osteoporosis guidelines.

Patients diagnosed with IBD and hyperoxaluria frequently experience fat malabsorption, thus requiring counseling on the matter.

Is supportive medical nutrition therapy (oral nutritional supplements, enteral nutrition, or parenteral nutrition) indicated in patients with inflammatory bowel disease (IBD)?

When medical nutrition is necessary in inflammatory bowel disease, oral nutritional supplements should be the initial approach as supportive therapy in conjunction with regular food.

If oral feeding alone is inadequate, enteral nutrition (EN) can be considered as supportive therapy. Generally, EN via formulas or liquids is preferred over parenteral nutrition (PN), unless the latter is completely contraindicated.

Exclusive enteral nutrition (EN) is effective and can be recommended as the first-line treatment to induce remission in children and adolescents with mild active Crohn’s disease (CD).

It is not recommended to use primary nutritional therapy (EN or PN) in the treatment of active UC in both adults and children.

Nasogastric or nasoenteric tubes, as well as percutaneous gastrostomy or jejunostomy, may be utilized for EN in IBD. It is recommended that enteral tube feeding in IBD should be administered through an enteral feeding pump, particularly if it is administered through a jejunal tube instead of a gastric tube.

Formulation Selection of Enteral Nutrition (EN) in Inflammatory Bowel Disease (IBD)

In active IBD, a standard EN formulation with moderate fat content (polymeric diet) should be used as the primary and supportive nutritional therapy. The use of specific formulations or substrates such as glutamine or n-3 fatty acids is not recommended in EN or PN therapy for patients with IBD. In cases of ongoing high output stomas, parenteral infusions of fluid and electrolytes may be necessary.

Indications for the implementation of parenteral nutrition (PN) in inflammatory bowel disease (IBD)

When it comes to IBD, there are certain indications that necessitate the implementation of PN. These include:

  1. cases where oral nutrition or EN is insufficiently viable (e.g., due to dysfunctional gastrointestinal tracts or in CD patients with short bowel syndrome)
  2. the presence of an obstructed bowel where it is impossible to place a feeding tube beyond the obstruction or previous attempts have been unsuccessful
  3. the occurrence of other complications such as an anastomotic leak or high-output intestinal fistula.

IBD patients with enterostoma

For patients with IBD experiencing severe diarrhea or those with a high output jejunostomy or ileostomy, it is recommended to monitor their fluid output and urine sodium levels. As a result, fluid intake can be adjusted accordingly. This may involve reducing hypotonic fluids and increasing saline solutions, while also restricting hypertonic fluids. Additionally, it is important to consider any food intolerances that may exacerbate fluid output. In cases where there are ongoing high output stomas, parenteral infusions of fluids and electrolytes may be required.

What are the specific nutritional recommendations for subgroups of inflammatory bowel disease (IBD)?

It is important to make every effort to prevent dehydration in patients with IBD. Patients who have CD and a low-output distal (low ileal or colonic) fistula can typically receive all necessary nutritional support through enteral nutrition, usually in the form of food.

Patients diagnosed with CD and exhibiting a high output fistula located in the proximal region are recommended to receive partial or complete parenteral nutrition for nutritional support.

For patients with IBD who have experienced prolonged nutritional deprivation, it is important to take standard precautions and interventions to prevent refeeding syndrome. This is especially important with regards to phosphate and thiamine levels.

The use of EN as supportive therapy is considered safe and is recommended according to standard nutritional practice for patients with severe UC. PN is typically not recommended for use in UC, except in cases where the patient cannot be effectively fed by other means.

Before scheduled surgery, it is important to evaluate the patient’s nutritional status. In cases of malnutrition or those at nutritional risk, dietary interventions such as nutritional therapy should be considered.

Patients undergoing elective surgery can follow an enhanced recovery after surgery (ERAS) protocol which includes avoiding preoperative fasting from midnight. In addition, patients may receive carbohydrate loading before surgery and are encouraged to resume oral intake as soon as possible after surgery.

During the preoperative period, it is important to adhere to the following guidance for metabolic and nutritional purposes:

  • Avoid long periods of preoperative fasting
  • Encourage early resumption of oral feeding after surgery
  • Incorporate nutrition into the patient’s overall management plan
  • Maintain metabolic control, such as monitoring blood glucose levels
  • Minimize factors that exacerbate stress-related catabolism or impair gastrointestinal function
  • Encourage early mobilization to promote protein synthesis and muscle function.

Patients who are malnourished or unable to resume oral intake within seven days after surgery should receive medical nutrition therapy, including enteral nutrition and/or parenteral nutrition as needed. Early initiation of therapy is crucial.

Encouragement to consume oral nutritional supplements (ONS) should be provided to patients who are unable to meet their energy and/or protein requirements from regular food during the perioperative period.

If malnutrition is diagnosed in patients with IBD, it is recommended to delay surgery for 7-14 days whenever possible. During this time, intensive medical nutrition therapy such as oral nutritional supplements (ONS), enteral nutrition (EN), and/or parenteral nutrition (PN) should be initiated to improve nutritional status before surgery.

The ESPEN working group has defined “severe” nutritional metabolic risk as meeting at least one of the following criteria:

  • Weight loss of >10-15% within 6 months
  • Body mass index (BMI) <18.5 kg/m2
  • Nutritional risk screening (NRS) >5. NRS includes assessment of the patient’s nutritional status (based on weight loss, BMI, and general condition or food intake) and disease severity (stress metabolism due to the degree of disease), and is associated with higher risk for adverse outcomes.
  • Serum albumin <3 g/dL (with no signs of hepatic or renal dysfunction)

If oral and enteral intake alone cannot meet the energy and/or nutrient requirements (<50% of the needs) for more than seven days, a combination of EN and PN should be considered.

PN should only be used as the sole intervention if EN is not feasible, such as due to the lack of access, severe vomiting, or diarrhea, or if it is contraindicated, such as due to intestinal obstructions or ileus, severe shock, or intestinal ischemia.

The enteral route is generally the preferred method, except when one or more of the following contraindications are present:

  • Intestinal obstruction or ileus
  • Severe shock
  • Intestinal ischemia
  • High output fistula
  • Severe intestinal hemorrhage

What nutritional interventions are recommended for patients with Crohn’s disease (CD) during the perioperative phase?

Early nutritional support should be provided to surgical patients with Crohn’s disease (CD), as it has been shown to reduce the risk of postoperative complications, regardless of the method of administration.

Patients with CD who experience prolonged gastrointestinal failure, such as those who have undergone intestinal resection resulting in short bowel syndrome, require PN for survival in the early stages of intestinal failure. Therefore, PN is considered mandatory in these conditions.

Are particular nutritional strategies required in patients with ulcerative colitis (UC) during the perioperative phase?

Patients with ulcerative colitis (UC) who are undergoing surgery should receive a personalized nutritional plan that takes into account their nutritional status and the severity of their disease.

What nutritional strategies should be considered during the postoperative phase for patients with inflammatory bowel disease (IBD)?

Patients with IBD in the postoperative phase can typically begin normal food intake, oral nutritional supplements, or enteral nutrition early after surgery. After proctocolectomy or colectomy, it is important to administer water and electrolytes based on individual needs to ensure hemodynamic stability.

There is no recommendation for using probiotics in the treatment of active CD, prevention of relapse in the remission phase, or postoperative recurrence of disease.

As per ulcerative colitis (UC), selected probiotics or probiotic-containing preparations can be considered as an alternative to standard therapy with 5-aminosalicylic acid (5-ASA) in patients with UC who have mild to moderate active disease and are unable to tolerate 5-ASA. Seven studies have reported the superiority of probiotics, including bifidobacteria-fermented milk, synbiotics, and selected multistrain probiotics, over placebo. However, two studies did not directly compare the active and control groups. Multistrain probiotics were predominantly used in most of these studies.

On the other hand, three studies showed no significant difference between patients treated with probiotics and those treated with placebo, and one study had a low completion rate with only 25 of 90 patients completing the study. In one study, a probiotic was found to be non-inferior to 5-ASA treatment, while in another study, the same probiotic was found to be inferior to placebo.

Multistrain probiotics may be considered as a preventative measure against pouchitis.

Prebiotic therapy should not be recommended for the treatment of CD, either in active disease or for the maintenance of remission. Therefore, no specific prebiotics can be recommended for CD in either phase. Routine use of prebiotic therapy cannot be recommended for the treatment of UC, whether for active disease or for maintenance of remission. Finally, there is currently no sufficient evidence to make recommendations for the use of prebiotic therapy in pouchitis.

There is no specific antibiotic regimen that can be recommended for the management of active CD or for maintenance of medically-induced remission in CD. Similarly, there is no antibiotic regimen that can be recommended for active UC, including acute severe disease, or for maintenance of remission in UC.

However, ciprofloxacin (first choice) and metronidazole can be considered as initial therapy in acute pouchitis. At present, there is no recommended antibiotic regimen for the prevention or management of chronic resistant pouchitis.

Fecal microbiota transplantation in inflammatory bowel disease (IBD)

Fecal microbiota transplantation (FMT) is a procedure that involves transferring fecal matter from a healthy donor into the gastrointestinal tract of a recipient to restore the normal microbial balance of the gut. The fecal matter is collected from a healthy donor, processed, and then either transplanted directly into the recipient’s colon or administered via a nasogastric tube or enema.

FMT is primarily used as a treatment for recurrent Clostridioides difficile infection (CDI), which is a bacterial infection that causes severe diarrhea and inflammation of the colon. However, research is being conducted to explore its potential therapeutic use in other conditions, such as inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS). At present no recommendation can be made for or against FMT in IBD.

How should patients with inflammatory bowel disease (IBD) modify their diet during the remission phase?

Patients with IBD should adhere to healthy dietary patterns and avoid any individual nutritional triggers. If any specific clinical issues persist during the remission phase, the diet should be adjusted accordingly.

For supporting the maintenance of remission in patients with IBD, n-3 fatty acid supplementation should not be advised. However, when more than 20 cm of the distal ileum, with or without the ileocecal valve, is removed or if vitamin B12 deficiency is confirmed, vitamin B12 supplementation should be administered to CD patients.

Selected patients with IBD, such as those treated with sulphasalazine and methotrexate, should receive prophylactic supplementation of vitamin B9/folic acid. In cases where malnutrition cannot be adequately addressed through dietary counseling, ONS or EN can be recommended to patients with CD in remission. However, neither EN nor PN should be recommended as a primary therapy for maintaining remission in IBD.

Endurance training should be encouraged in all patients with IBD. Patients with IBD who have decreased muscle mass and/or muscle performance should be recommended appropriate physical activity, mainly resistance training.

What dietary recommendations should be given to obese patients with inflammatory bowel disease (IBD)?

Obese patients with IBD should be advised to focus on weight reduction only during phases of stable remission and in accordance with current obesity guidelines.

Are there special dietetic recommendations for pregnant and breastfeeding patients with inflammatory bowel disease (IBD)?

Regular monitoring of iron status and folate levels is recommended for pregnant patients with IBD, and supplementation of iron and/or vitamin B9/folic acid should be provided if deficiencies occur. For breastfeeding patients with IBD, regular monitoring of their nutritional status is recommended, and supplementation should be provided if deficiencies are identified.

Bottom line

In conclusion, nutrition plays a crucial role in the management of inflammatory bowel disease (IBD). Patients with IBD should receive individualized dietary counseling based on their clinical status, disease phenotype, and nutritional status. In general, patients should follow the principles of healthy dietary patterns, avoid individual nutritional triggers, and adjust their diet according to particular clinical problems.

Specific nutrients, such as vitamin B12, vitamin B9/folic acid, iron, and n-3 fatty acids, should be supplemented in selected patients with deficiencies. Physical activity, particularly endurance and resistance training, is recommended for all patients with IBD.

Further research is needed to better understand the role of nutrition in the pathogenesis and management of IBD.


  1. Bischoff SC, Bager P, Escher J, et al. ESPEN guideline on Clinical Nutrition in inflammatory bowel disease. Clin Nutr 2023;42:352-379.
Last update: 14 April 2024, 20:42


Gastroenterologist - Hepatologist, Thessaloniki

PhD at Medical School, Aristotle University of Thessaloniki, Greece

PGDip at Universitair Medisch Centrum Utrecht, The Netherlands

Ex President, Hellenic H. pylori & Microbiota Study Group