How to Gain Weight With Crohn's Disease
Weight loss is one of the three most common symptoms of Crohn's disease, along with diarrhea and belly pain, according to NIDDK. Getting the weight back takes two things working together: treatment that calms the inflammation, and enough calories and protein from foods your gut can handle. This guide covers both, with guideline-based calorie and protein targets and food choices for flare days.
- Inflammation can cut nutrient absorption, so keeping treatment on track is part of the plan.
- Eat smaller meals more often and pick calorie- and protein-rich foods you tolerate.
- With active disease, ESPEN raises protein to 1.2 to 1.5 grams per kilogram a day.
- Ask for a registered dietitian.
Why Crohn's disease causes weight loss
NIDDK describes several ways Crohn's disease affects nutrition. Symptoms may cause some people to lose their appetite and eat less. Inflammation in the small intestine may cause the body to absorb fewer nutrients. And certain medicines and surgery used to treat Crohn's may also cause the body to absorb fewer nutrients.
The American Gastroenterological Association's (AGA) 2024 clinical practice update adds that dietary restrictions, along with the complications of IBD, can result in malnutrition, which it calls underrecognized. The guideline from the European Society for Clinical Nutrition and Metabolism (ESPEN) notes that Crohn's disease can come with malabsorption or maldigestion. NIDDK lists malnutrition among Crohn's complications, and in children, problems with growth such as gaining less weight than normal.
Treatment comes first
According to NIDDK, the goals of Crohn's treatment are to lower inflammation in your intestines, prevent flares of your symptoms and keep you in remission. Medicines do not cure Crohn's disease, but they can reduce inflammation and bring on and maintain remission. Surgery can treat complications and improve symptoms when medicines are not enough.
Nutrition can be a treatment too. The NHS notes that some people may be offered a special liquid diet, called enteral nutrition, instead of medicines, for example children or people who cannot take steroids. The AGA calls exclusive enteral nutrition an effective therapy for bringing on remission, with stronger evidence in children than adults. These are medical treatments your team directs, not do-it-yourself diets.
Your calorie and protein target
See the numbers a clinical nutrition guideline starts from. For adults only; children need targets from their pediatric team.
Your starting targets
Starting ranges from the ESPEN guideline for adults with inflammatory bowel disease (IBD). When a different energy need is suspected, ESPEN says to measure it with indirect calorimetry and an individual activity factor, so your dietitian may set other numbers.
Where the numbers come from
ESPEN's 2023 guideline on clinical nutrition in IBD says energy needs in IBD are similar to those of the healthy population and that, in general, energy delivery should be 30 to 35 calories per kilogram a day. Protein needs rise in active IBD, to 1.2 to 1.5 grams per kilogram a day in adults; in remission, about 1 gram per kilogram is recommended.
The optional gain setting adds 300 or 500 calories, from the NHS general advice for adults who want to gain weight. It is not specific to Crohn's disease, so check it with your team, especially during a flare. Example: a 150-pound (68 kg) adult with active disease gets 2,041 to 2,381 calories and 82 to 102 grams of protein a day, or about 340 to 397 calories and 14 to 17 grams of protein at each of six meals.
Eating to regain weight
MedlinePlus, the National Library of Medicine's consumer health site, gives simple rules for Crohn's disease: eat a well-balanced diet, get enough calories, protein and nutrients from a variety of food groups, eat smaller meals more often, and drink plenty of liquids.
To add calories, the NHS suggests adding cheese, nuts and seeds to meals and having high-calorie drinks such as milkshakes between meals. Choose what your gut tolerates: nuts, seeds and beans are among the higher-fiber foods a low-fiber diet leaves out during a flare. If food is not enough, ESPEN says oral nutritional supplements are the first step, taken in addition to normal food. Longer term, the AGA advises a Mediterranean-style diet with fruits, vegetables, monounsaturated fats, complex carbohydrates and lean proteins, low in ultraprocessed foods, added sugar and salt, unless there is a reason not to.
Calorie and protein foods that fit a low-fiber day
Every food below fits a food group that the MedlinePlus low-fiber diet allows: eggs, smooth peanut butter, milk products, fish, poultry, tofu, refined grains with less than 2 grams of fiber per serving, potatoes without skin, canned or very ripe fruit, and oils. Values are from USDA FoodData Central.
| Food | Portion | Calories | Protein | Fiber |
|---|---|---|---|---|
| Mashed potatoes with milk and butter | 1 cup | 237 | 3.9 g | 3.1 g |
| White rice, cooked | 1 cup | 205 | 4.2 g | 0.6 g |
| Peanut butter, smooth | 2 tbsp | 191 | 7.1 g | 1.6 g |
| Scrambled eggs | 2 large | 182 | 12.2 g | 0.0 g |
| Salmon, Atlantic, cooked | 3 oz | 175 | 18.8 g | 0.0 g |
| Greek yogurt, plain, whole milk | 6 oz | 165 | 15.3 g | 0.0 g |
| Chicken breast, roasted | 3 oz | 140 | 26.4 g | 0.0 g |
| Olive oil | 1 tbsp | 119 | 0.0 g | 0.0 g |
| Cheddar cheese | 1 oz | 114 | 6.5 g | 0.0 g |
| Banana | 1 medium | 105 | 1.3 g | 3.1 g |
| Tofu, firm, calcium-set | 1/2 cup | 98 | 11.4 g | 1.1 g |
| White bread | 1 slice | 77 | 2.6 g | 0.8 g |
| Canned peaches in juice | 1/2 cup | 55 | 0.8 g | 1.6 g |
Source: USDA FoodData Central, SR Legacy. If you are lactose intolerant, MedlinePlus suggests lactose-free products. More ideas: gaining weight with a small appetite.
Flare days and strictures
NIDDK says researchers have not found that specific foods cause or worsen Crohn's symptoms, but your doctor may suggest a food diary to spot foods that seem to make them worse. MedlinePlus has three tips for problem foods:
- Fiber. Too much fiber may make symptoms worse. Try baking or stewing fruits and vegetables if eating them raw bothers you, and eat low-fiber foods if that does not help enough.
- Dairy. If your body does not digest dairy well, limit it and try low-lactose cheeses such as Swiss and cheddar, or an enzyme product that helps break down lactose.
- Gas. Avoid foods known to cause gas, such as beans, spicy food, cabbage, broccoli, cauliflower, raw fruit juices and fruits, especially citrus fruits.
MedlinePlus says you do not need a low-fiber diet for IBD unless you have a flare or a history of stricture, a narrowing of the bowel. With a stricture, you may be put on a low-residue diet. The AGA says people with symptomatic strictures may not tolerate raw fruits and vegetables, and that careful chewing and cooking them to a soft consistency can help keep more in the diet. ESPEN also supports a diet with adapted texture when strictures cause obstructive symptoms.
Vitamins, minerals and bones
ESPEN recommends checking people with IBD for micronutrient deficiencies regularly, including in remission. The AGA says all patients with IBD should be monitored for vitamin D and iron deficiency, and that people with extensive ileal disease or prior ileal surgery should be monitored for vitamin B12 deficiency.
NIDDK notes that Crohn's disease may lead to more than one type of anemia, including iron-deficiency anemia and vitamin B12 deficiency anemia, and that doctors may recommend calcium and vitamin D supplements or medicines to prevent or slow bone loss. For safety reasons, NIDDK advises talking with your doctor before using any dietary supplement.
When to call your care team
MedlinePlus lists weight loss in everyone, and failure to gain weight in children, among the reasons to call your provider, along with diarrhea that diet changes and medicines cannot control. The NHS advises seeing a GP if your symptoms get worse or treatments are not helping.
The AGA recommends regular malnutrition screening in IBD, looking for unintended weight loss, fluid retention and loss of fat and muscle, with a fuller evaluation by a registered dietitian when these show up, and suggests that everyone newly diagnosed with IBD have access to a dietitian. For children, ESPEN recommends exclusive enteral nutrition as a first-line treatment in mild active Crohn's disease, so a child needs a pediatric plan, not the adult numbers here.
Frequently asked questions
- Why do people with Crohn's disease lose weight?
- NIDDK lists three reasons: symptoms can reduce appetite, inflammation in the small intestine can reduce nutrient absorption, and some medicines and surgery can also reduce absorption.
- How can I gain weight with Crohn's disease?
- Keep treatment on track, eat smaller meals more often, and choose calorie- and protein-rich foods you tolerate. Ask your team about oral nutritional supplements and a registered dietitian.
- How much protein do I need with Crohn's disease?
- The ESPEN guideline recommends 1.2 to 1.5 grams of protein per kilogram of body weight a day for adults with active IBD, and about 1 gram per kilogram in remission. For a 150-pound (68 kg) adult with active disease that is about 82 to 102 grams a day.
- What can I eat to gain weight during a Crohn's flare?
- Lower-fiber foods that still bring calories and protein: eggs, smooth peanut butter, yogurt or cheese if you tolerate dairy, fish, chicken, tofu, white rice and potatoes without skin, with olive oil stirred in.
- Do nutrition shakes help with Crohn's weight loss?
- They can. ESPEN says oral nutritional supplements are the first step when medical nutrition is needed in IBD, taken in addition to normal food. Enteral nutrition used as a treatment is a therapy your team directs.
- Is there a special diet for Crohn's disease?
- ESPEN says there is no IBD diet that can be generally recommended to promote remission in active disease. The AGA advises a Mediterranean-style diet for overall health, and therapies such as the Crohn's disease exclusion diet are done with a registered dietitian.
Keep reading
References
Sources: NIDDK: Eating, Diet, and Nutrition for Crohn's Disease · NIDDK: Symptoms and Causes of Crohn's Disease · NIDDK: Treatment for Crohn's Disease · NIDDK: Definition and Facts for Crohn's Disease · MedlinePlus: Crohn disease, discharge · MedlinePlus: Low-fiber diet · ESPEN guideline on clinical nutrition in IBD (2023) · AGA Clinical Practice Update on Diet and Nutritional Therapies in IBD (2024) · NHS: Crohn's disease · NHS: Healthy ways to gain weight · USDA FoodData Central.