Malnutrition and IBD: What You Need to Know

Getting enough nutrients can be challenging when you live with Crohn’s disease or ulcerative colitis, especially when symptoms make it difficult to eat, digest, or absorb food. 

Over time, these challenges can put people with IBD at risk for malnutrition, a condition that occurs when the body doesn’t get enough of the calories, protein, vitamins, or minerals it needs to stay healthy.

“You don’t have to be underweight to experience malnutrition. People with IBD can have nutritional deficiencies or inadequate nutrient intake at any body size,” said David Gardinier, a registered dietitian with The Cleveland Clinic and member of the Crohn's & Colitis Foundation’s National Scientific Advisory Committee. 

Why Does IBD Increase the Risk of Malnutrition? 

Several factors related to IBD can make it harder to meet nutritional needs.

Inflammation and Nutrient Absorption 

Inflammation can affect nutrient absorption. Inflammation in the small intestine can interfere with digestion and the absorption of nutrients, while inflammation in the large intestine can affect the absorption of water and electrolytes. Iron is an example of a nutrient where absorption goes down when inflammation is high. 

IBD Symptoms and Food Restriction 

Symptoms can make eating and retaining fluids difficult. Abdominal pain, nausea, diarrhea, and frequent bowel movements may reduce appetite. Symptoms can cause someone to eat less because they are worried about worsening their pain, nausea or bowel movements. Severe diarrhea can also cause the body to lose fluids and electrolytes.

Food restriction can play a role. People may begin avoiding foods they believe trigger symptoms. While identifying foods that worsen your symptoms can be helpful, the Foundation recommends working with your healthcare team to find an eating pattern that meets your individual nutritional needs.  

Medications and Surgery 

Some medications can also affect nutrition. For example, certain medications can interfere with nutrient absorption or affect muscle and bone health.  

Learn more about malnutrition and IBD, and other diet and nutrition topics. 

What Are the Signs of Malnutrition in People With IBD? 

Malnutrition isn't always easy to recognize. Some nutritional deficiencies may not cause obvious symptoms at first. 

Possible signs include: 

• Unintentional weight loss
• Fatigue or low energy
• Weakness
• Loss of muscle mass
• Eating very little or severely restricting your diet
• Vitamin or mineral deficiencies  

If you or your child is experiencing these changes, talk with your healthcare provider. Blood tests and other assessments can help identify nutritional deficiencies and determine whether additional support is needed. 

How Can Malnutrition Affect People With IBD? 

Getting adequate nutrition is an important part of managing IBD. Jacqueline Park, who lives with inflammatory bowel disease, was diagnosed in 2020 after a sudden onset of symptoms.  

“One of the first indicators that something was wrong was my weight loss,” she shared. After her diagnosis, it took some time to find the right treatment for her disease. “I couldn’t stomach really any food at all. Being underweight impacted me in significant ways. I was so exhausted and lost interest in my hobbies.” 

Watch the MyIBD Learning Webinar on “Malnutrition in IBD.” 

How Can Malnutrition Be Prevented or Managed With IBD? 

“There isn't one diet that works for everyone with IBD,” noted Gardinier. “But addressing malnutrition should always be a nutritional priority.  

Your nutritional needs can change depending on your disease activity, symptoms, medications, surgeries, and other factors. 

A few important steps include: 

Get screened for nutrient deficiencies. Your healthcare team may recommend routine testing even if you don't have obvious signs of malnutrition.  

Avoid unnecessary food restrictions. If certain foods worsen your symptoms, talk with your care team about alternatives that can provide similar nutrients. 

Work with an IBD-focused registered dietitian. An IBD dietitian can help identify and treat malnutrition, monitor nutrient deficiencies, develop individualized nutrition strategies, and help you expand your diet when possible.  

Remember that nutrition is part of your IBD care. The goal isn't simply to find a list of “good” or “bad” foods. It's to develop an eating pattern that meets your nutrient needs while taking your symptoms and individual needs into account.

When Should I Talk to My Healthcare Team? 

If you're losing weight without trying, struggling to eat enough, limiting your diet to only a few foods, experiencing persistent diarrhea, or feeling unusually weak or fatigued, bring it up with your IBD care team. 

“I always encourage my patients who have IBD to get routine vitamin panels to look for vitamin and mineral deficiencies so we can intervene early if they are at risk,” noted Dr. Greg Cammell, a gastroenterologist who also lives with IBD. 

You don't have to figure out nutrition on your own. Your gastroenterologist, registered dietitian, and other members of your healthcare team can help identify nutritional risks and create a plan that works for you. 

“Nutrition is one piece of the IBD puzzle,” said Gardinier. “The overall goal is to find an eating pattern that provides good nutrition to the body, minimizes symptoms, and is personalized to each individual’s unique lifestyle. 

Have questions about nutrition? Call the Foundation’s IBD Help Center to get personal answers from information specialists. Chat is available Monday, Tuesday, and Thursday from 9 a.m. to 5 p.m. EST.   

Reviewed by David Gardinier, registered dietitian with The Cleveland Clinic and a Crohn's & Colitis Foundation National Scientific Advisory Committee member