Crohn’s disease diet: what to eat during a flare-up and remission

What can you eat with Crohn’s disease?

In remission, the plan widens according to what you tolerate and the needs of your case. Spanish specialists in inflammatory bowel disease recommend a Mediterranean pattern, with fresh fruit and vegetables, monounsaturated fats such as olive oil, complex carbohydrates and few ultra-processed foods [2].

There is no list of foods you must remove because you have Crohn’s.

What does exist are individual intolerances, and they are found one by one. Remove only what makes you feel unwell each time you eat it, and try it again after some time. Many people tolerate in remission what they do not tolerate during a flare-up.

It is worth knowing how far this goes. A 2025 European consensus does not find enough evidence to use the Mediterranean diet as maintenance treatment in Crohn’s disease [3]. It is recommended because it is a good way of eating, not because it slows the disease.

If you are in a flare-up

During a flare-up four things change, and none of them means stopping eating.

Texture and fibre. During a flare-up do not cut out fibre as a rule. If you have a stricture with obstructive symptoms, your team may temporarily adapt the texture and consider a low-residue diet [1] [3]. Widen the variety again as you tolerate it.

Volume. If large meals bother you, splitting them into smaller portions can help.

Protein. Increase it. The European clinical nutrition guideline puts needs at 1.2-1.5 g per kilo of body weight a day during a flare-up, compared with around 1 g in remission [1].

Fluids. If you have severe diarrhoea or a high-output stoma, the ESPEN guideline recommends that your team monitors losses and urinary sodium and adapts fluids. Saline solutions may be part of that individual plan [1].

Also avoid restrictive diets [2]. Eating little and with little variety during a flare-up can favour malnutrition, which worsens the course of the disease, complications and quality of life [1].

Are there foods you cannot eat with Crohn’s?

No. Closed lists of foods that cannot be eaten do not come from any consensus guideline. They come from adding up the intolerances of many different people.

What guidelines do support is shorter. Specialists advise limiting regular consumption of ultra-processed foods within a varied diet [2]. For the rest (lactose, spices, fried foods, foods that cause gas or a lot of fibre), the data only support removing them when they are poorly tolerated [1].

Removing foods without a reason can cause deficiencies that will later need correcting. If bloating is what bothers you most, the guide on abdominal bloating explains what causes bloating and what does not.

A low-FODMAP diet does not treat the inflammation. It can be considered if the disease is inactive and functional symptoms similar to those of irritable bowel syndrome persist [3]. The FODMAP guide explains why the elimination phase is temporary and must include reintroduction.

Do you need to avoid gluten and dairy?

Not because you have Crohn’s. Without a coeliac disease diagnosis or suspicion of gluten sensitivity, there is no consistent evidence to remove it [2]. If you suspect coeliac disease, consult before changing your diet so that your team can arrange the tests [2].

Dairy is only limited during a flare-up if it increases your diarrhoea every time you have it [2]. Removing it out of habit has a cost. The European clinical nutrition guideline counts avoiding dairy among the risk factors for low bone density, that is, more fragile bones [1].

If lactose bothers you, yogurt and aged cheeses contain much less; you can discuss other lactose-free options with your team.

What if I have lost weight and cannot regain it?

This is very common in Crohn’s. Weight is regained by eating more often and with dishes that provide more energy in less volume. Raw olive oil over the plate, avocado, egg, cheese and ground nuts if you tolerate them. It also helps not to fill up on water just before eating.

There are two resources that are decided with your team and not on your own. The first is oral nutritional supplements, complete formulas added to normal food when support is needed [1]. The second is exclusive enteral nutrition, which means feeding only on a formula for the period your team specifies [3].

The ECCO consensus considers exclusive enteral nutrition effective for inducing remission regardless of age [3]. In adults with mild active Crohn’s, ESPEN notes that its effect is lower than drug treatment and does not recommend it as first-line; it may be considered if the person does not tolerate or refuses that treatment [1].

The indication, the formula and the duration are decided with the clinical team.

In mild or moderate flare-ups, an exclusion diet for Crohn’s disease is also considered, together with partial enteral nutrition, in adults with mild or moderate Crohn’s [3].

The 2023 ESPEN guideline accepted the exclusion diet with or without this nutrition [1], while the 2025 ECCO consensus considers the evidence insufficient to use it without it [3]. Neither is improvised at home. They are prescribed and followed with your team.

If you take corticosteroids, be aware that they also increase protein loss [1].

Do supplements help?

Less than is often thought. The European clinical nutrition guideline in inflammatory bowel disease is clear about the most popular ones [1].

• Probiotics. They are not recommended in Crohn’s, either during a flare-up or to prevent relapses or recurrence after surgery [1].
• Omega-3. They should not be advised to maintain remission. It is one of the firmest recommendations in the guideline [1].
• Glutamine. It is not recommended to add it to enteral or parenteral nutrition [1].
• Prebiotics. They are not recommended either, during a flare-up or to maintain remission [1].

What is supplemented is what is missing and has been measured. Your doctor or dietitian-nutritionist will decide whether supplementing is needed after reviewing your blood test results [1]. If you were looking for something to reduce bloating, the anti-inflammatory diet guide explains what can be expected from that approach.

Which nutrients are monitored in Crohn’s disease?

The nutrients that may be low because of inflammation, diarrhoea or surgery. They are checked in blood tests also in remission, and each deficiency is corrected separately, with your doctor [1].

• Iron. Anaemia from iron deficiency is one of the most common deficiencies. When the disease is quiet, your doctor usually prescribes oral iron. If the disease is active, you did not tolerate oral iron or haemoglobin is below 100 g/L, your doctor usually prescribes it intravenously [1].
• Vitamin D. It is measured if you are in a flare-up, take corticosteroids or it is suspected to be low, and supplemented with calcium if needed [1]. If you take corticosteroids, calcium and vitamin D are given together [2]. There is no evidence that taking it helps you get out of a flare-up [3].
• Vitamin B12 and folic acid. B12 is given if more than 20 cm of the distal ileum has been resected or if a deficiency is confirmed. Folic acid, if you take sulfasalazine or methotrexate [1].

Oily fish can be part of a varied diet if you tolerate it. Eating it as food is not the same as using capsules to maintain remission [1].

With fibre in remission, neither low- nor high-fibre diets have been shown to maintain remission [3]. The sensible approach is to return to your usual amount as you tolerate it. To induce remission, there is no evidence for resistant starch supplements in Crohn’s [3].

If you have a stricture

A stricture is a narrowing of the intestine, and it changes the plan. If there are obstructive symptoms, your team may indicate an adapted texture [1]. Reducing the bulk-forming fibre could lower the risk of obstruction, although there is no data proving it [3].

Without a stricture, on the other hand, there is no need to limit fibre [2]. That is why two people with the same disease can leave clinic with opposite plans.

What mistakes do we see in clinic?

• Following the flare-up plan once you are in remission. If you needed a temporary soft texture, review it when you improve: keeping restrictions can leave out foods you already tolerate.
• Cutting out foods out of fear and never trying them again. One after another, until you eat the same things and end up short of iron, calcium or protein.
• Starting supplements on your own. Probiotics or glutamine that nobody has prescribed, while iron or vitamin D that nobody has measured is low.

And if what I have is not Crohn’s?

Some people come here with symptoms and without a diagnosis. Crohn’s disease is not diagnosed from symptoms or with a trial diet. Medical assessment combines history and examination with tests depending on the case; these can include blood tests, faecal calprotectin, endoscopy, biopsies or imaging [2].

Pain and diarrhoea are shared with irritable bowel syndrome, gastritis and infection, and each is treated differently. If what you have is heartburn or stomach pain, start with the gastritis guide. If what you have been diagnosed with is ulcerative colitis, its guide covers what to eat according to the phase.

Without a diagnosis, the first step is your doctor.