Key takeaways

  • Cystic fibrosis (CF) is a genetic disease that causes a buildup of mucus in organs throughout the body. Stool, or feces, can indicate how your gastrointestinal tract is functioning and whether treatment is necessary.
  • CF can cause stool to be bulky, greasy, and foul-smelling. It may be pale or clay colored, and it can be difficult to pass.
  • Dietary changes and pancreatic enzyme replacement therapy (PERT) may help manage stool changes with CF.

Cystic fibrosis (CF) is an inherited disorder in which mucus builds up in various parts of the body, including the respiratory and digestive systems.

Over time, the thick and sticky mucus can cause cysts and scar tissue in the organs. When this affects your gastrointestinal tract, you can have trouble getting nutrition from foods, and you may see changes in bowel movements.

Here’s more about what your stool may look like if you have CF, what causes these changes, and what treatments may help.

If you have CF, you may experience a range of bowel movement types, from loose stools to constipation and even intestinal blockages.

CF stools may be:

CF is caused by inherited changes to a gene called the CFTR gene. Changes in this gene affect how the CFTR protein in the cells works, making it less effective.

Usually, this protein moves salt in and out of cells to balance moisture levels. In CF, this process does not work properly. This leads to a lack of moisture, which can cause mucus to be thicker and stickier. Thick and sticky mucus can build up in the body.

One organ where mucus can accumulate is the pancreas. When your pancreas isn’t functioning optimally, this can lead to digestive problems. More specifically, your body can’t absorb important nutrients from foods and drinks.

Impaired digestion means that foods move through your gastrointestinal tract without being properly broken down and absorbed. Stools may be bulkier, smellier, or greasier as a result.

Dietary changes may help with nutrient absorption and bowel movements. Experts recommend eating a balanced diet that includes:

  • fruit
  • vegetables
  • whole grains
  • eggs
  • seafood
  • beans
  • dairy
  • meats
  • nuts
  • seeds

Doctors may also suggest that you eat high energy, high fat, and high protein foods.

Supplementation with vitamins is another potential treatment, whether you take them orally (by mouth) or enterally (tube feeding). A doctor can provide more information about any supplements that they recommend based on individual circumstances.

Doctors may also prescribe pancreatic enzyme replacement therapy (PERT). Taking enzymes with meals and snacks may help with stool symptoms. PERT is also essential for avoiding vitamin deficiencies and malnutrition, as well as promoting healthy weight gain.

The stools themselves are not harmful. However, stools serve as an indicator of how well the digestive tract and pancreas are functioning.

CF-related diabetes is another potential complication related directly to the pancreas. With CF, your pancreas may not produce enough insulin hormone needed to regulate blood sugar. This condition affects between 40% and 50% of adults with CF.

Symptoms of CF, including digestive symptoms, typically appear soon after birth into early childhood.

Between 65% and 100% of people with CF experience digestive issues. And about 80% to 90% of people require PERT.

Aside from stool changes, symptoms of CF may include gas, bloating, cramping, and abdominal pain. These symptoms may also be a sign of CF-related complications, such as DIOS.

Contact your doctor if you notice changes in your bowel movements. Bulky, foul-smelling, or greasy stools may be a sign of cystic fibrosis or other digestive problems.

If you have already been diagnosed with CF, stool changes may indicate how well your body is processing the foods you eat.

Eating a balanced diet and taking PERT and additional supplements may help you reach a healthy weight, maintain adequate nutrition, and avoid other symptoms. Your doctor can provide treatment recommendations based on your individual circumstances.

If you have cystic fibrosis (CF), you may experience bulky, greasy, or foul-smelling stool. This can indicate how well your digestive tract and pancreas are working.

Dietary changes can help manage stool changes, and pancreatic enzyme replacement therapy (PERT) can help with nutrient absorption.

Speak with a doctor if you have concerns about stool changes or other symptoms of CF. They can help create a suitable treatment plan or make changes to an existing plan, helping manage stool changes and reducing the risk of CF complications.