Crohn’s disease can cause weight loss and make maintaining weight more difficult. Keeping a food journey, making dietary changes, and working with a nutritionist are some ways to help prevent further weight loss.

Crohn’s disease is a form of inflammatory bowel disease (IBD). It can cause several gastrointestinal symptoms, such as nausea, vomiting, and abdominal pain and cramping.

Many people also find that certain foods can worsen symptoms, which may lead to self-restrictive diets. These factors, along with certain medication use, can contribute to weight loss.

This article explores the prevalence of weight loss and Crohn’s disease, reasons for potential weight loss, the role of obesity in Crohn’s disease, and tips for maintaining weight.

Weight loss is a systemic manifestation of Crohn’s disease, particularly during active phases or flares. It is one of the most common symptoms of this condition.

In a 2014 study involving 494 people with IBD, researchers noted that about 57% of the people reported significant weight loss at the time of diagnosis.

A 2020 review of studies noted that weight loss may vary.

The researchers stated that previous studies reported that 70% to 80% of people with IBD receiving in-patient care experience weight loss. IBD includes Crohn’s disease and ulcerative colitis, so this number does not reflect people with Crohn’s disease specifically.

The researchers also noted that 20% to 40% of people with Crohn’s disease who receive care in an outpatient facility report weight loss.

They also reported that malnutrition occurs frequently in IBD but that it appears more commonly in people living with Crohn’s disease.

Crohn’s disease can cause weight loss in several ways, such as:

  • malnutrition
  • reduced appetite or fear of eating
  • loss of nutrients, which can be due to symptoms such as chronic diarrhea

A 2020 literature review noted that 20% to 85% of people with IBD experience malnutrition and that it is more common in people with Crohn’s disease than those with ulcerative colitis. It can occur due to inadequate nutrient absorption (malabsorption), limited diet, and eating less.

Crohn’s disease affects the mucosal barrier responsible for absorbing key nutrients. If this mucosal barrier is not present, it leads to a person becoming nutrient deficient.

People with Crohn’s disease may also experience blood loss, vomiting, or diarrhea, which can contribute to weight loss and malnutrition. These symptoms may also contribute to a reduced appetite, which can result in eating less.

Diet and medications

Medications to treat Crohn’s disease can cause different side effects. Some drugs, such as corticosteroids, can lead to weight gain.

However, other medications, such as immunosuppressants, can cause nausea, vomiting, or other side effects that can result in weight loss.

Diet can also affect symptoms and disease progression. Therefore, people with Crohn’s disease may benefit from avoiding certain foods.

It is important that people with Crohn’s discuss dietary changes with a doctor or nutritionist. They can help people create an eating plan to help avoid unplanned weight loss and prevent malnutrition.

A person who experiences weight loss due to Crohn’s disease may be able to take steps to help maintain their current weight.

One example is keeping a food journal. An individual can record the foods they eat and how they make them feel or how they affect their symptoms.

This process can help someone determine what foods work for them. It can also allow them to provide useful information to their doctors about how foods affect them.

They can then build a dietary plan around foods that work for them, which may help them maintain or gain weight.

There is no specific diet that helps every individual with Crohn’s disease. However, limiting sugar intake and trigger foods may help some people to manage their symptoms.

In some cases, a doctor may recommend a higher calorie eating plan. This may help a person maintain their weight at diagnosis or regain weight.

Evidence suggests that people with obesity may have an increased risk of developing Crohn’s disease.

In a 2022 analysis of five cohort studies, researchers found that people with obesity had a higher risk of developing Crohn’s disease later in life compared with people without obesity. They noted that obesity is a risk factor for Crohn’s disease but not ulcerative colitis.

A 2023 study examined population data of 39,717,520 adults with IBD from 2010 to 2019. Of those with Crohn’s disease, 36.9% had obesity.

However, obesity and some metabolic complications were higher among people with ulcerative colitis than those with Crohn’s disease.

The researchers suggested that potential causes for increasing diagnoses of obesity in people with Crohn’s disease include dietary habits, prescribed steroid use, and an increase in smoking.

The researchers highlighted that obesity may be a cause, comorbidity, or consequence of IBD and that its potential complications and effect on disease burden require further consideration.

Weight loss is a common symptom of Crohn’s disease. It may occur due to malabsorption, nutrient loss, or not eating enough food. It may also occur as a side effect of medication or a response to symptoms such as abdominal pain, nausea, or vomiting.

A person with obesity may have an increased risk of developing Crohn’s disease later in life. However, more research is necessary to understand how living with obesity affects condition progression or treatment.

When a person with Crohn’s disease is losing weight, there are steps that they can take to help maintain their weight, including keeping a food journal, making doctor-recommended dietary changes, or working with a nutritionist to develop a supportive dietary plan.