How does cystic fibrosis affect the gastrointestinal tract?

Cystic fibrosis (CF) is most commonly considered to affect the lungs, but this genetic disease involving body secretions also affects the pancreas and digestive system. Ensuring that patients with CF receive good nutrition is therefore essential for helping to support their quality of life.1


CF is a genetic disorder that affects the respiratory, digestive and reproductive systems, and involves the production of abnormally thick mucus linings in the lungs and other organs. An individual must inherit two defective cystic fibrosis genes – one from each parent – to acquire this disease.1

Each time two carriers of CF conceive, there is a:1

  • 25% chance of passing CF to their children
  • 50% chance that the child will be a carrier of the CF gene
  • 25% chance that the child will be a non-carrier

CF is most common in North America and Europe, where it affects one in every 2000–3500 babies.1


People with CF have a variety of symptoms. The respiratory system is largely affected where mucus build-up can cause persistent coughing, wheezing and shortness of breath, combined with an increased risk of respiratory infections.

Excessive mucus can also affect the digestive system, causing a deficit of enzymes released by the pancreas that aid digestion. The result is reduced absorption of nutrients, greasy, bulky stools and intestinal blockage – as well as poor weight gain and growth in infants.

People with CF are also at higher risk of diabetes. Other symptoms of CFs include reproductive problems in both men and women, excessive salt content of an individual’s sweat and lower bone density.2*


For people with CF it is important to consider lifestyle changes to protect their health, including keeping vaccines that help prevent respiratory infections up-to-date, avoiding smoke, frequent hand washing, and increased calorie and nutritional intake.3

As mucus build-up can prevent proper absorption of nutrients, eating a high-calorie, high-fat and high-protein diet can help prevent decreased weight gain and slow growth in infants. Staying well hydrated and getting sufficient levels of salt are both important as well, as the changes in the secretory function cause more salt to be excreted in the sweat.3

Since good nutrition may help patients manage CF, at Nestlé Health Science, we are committed to research in the nutritional management of this and other genetic diseases which may help improve their quality of life.3


  1. World Health Organization. Genes and human disease: Cystic fibrosis. Available at: Accessed October 2018.
  2. National Heart, Lung and Blood Institute. Cystic fibrosis. Available at: Accessed October 2018.
  3. Mayo Clinic. Cystic fibrosis. Available at: Accessed October 2018.

Footnotes and abbreviations:
*Listed symptoms are not all inclusive; actual patient symptoms may vary.
CF, cystic fibrosis

Read more
Physical therapy for respiratory problems


Due to the buildup of excessive mucus in the lungs, cystic fibrosis is associated with respiratory problems like shortness of breath. Breaking up and clearing this mucus in the throat is a primary goal of chest physical therapy, which can involve different techniques or devices.1

  1. Accessed December 2014.
Ways to deal with digestive problems


Cystic fibrosis limits the amounts of nutrients absorbed by the digestive tract. Besides the oral intake of enzymes, nutritional management including supplementation of vitamins A, D, E, and K and high-calorie, high-fat and high-protein supplements can help to make up for nutritional deficits.1

  1. Accessed December 2014.