What to Know About Diet if You Have Cystic Fibrosis

Medically Reviewed by Poonam Sachdev on November 02, 2021
3 min read

Eating well is essential for people with Cystic Fibrosis. They can burn more calories than the average person and have to eat more than average to maintain a healthy weight. Their bodies don’t completely absorb all the energy they get from the food they eat. Knowing how and what to eat when you have cystic fibrosis can go a long way towards keeping your body strong and free from infections. 

‌Cystic Fibrosis, or CF, is a genetic disorder that can cause damage to major organs such as the lungs and the digestive system. In cystic fibrosis, mucus, sweat, and digestive juices become sticky and thick, clogging up tubes, ducts, and other passages. These clogs chiefly occur in the lungs and the pancreas, causing respiratory infections and difficulty digesting food or absorbing nutrients from the food. 

People with cystic fibrosis have specific dietary requirements that they need to meet.

‌If your body is burning more calories than it needs to maintain a healthy weight, it can make it hard to fight infections and maintain healthy lungs.

So, people with cystic fibrosis need up to 1½ times more calories than people without the disease. These energy requirements can increase if you’re fighting an infection.

Adults with cystic fibrosis should aim to maintain their body weight or increase it if they're under their recommended weight. The ideal cystic fibrosis diet should contain a lot of calories and fats, which are essential for the absorption of fat-soluble vitamins. Fats should make up 40% of your calories. 

Your doctor will help you figure out your ideal body weight.

‌People with cystic fibrosis should focus on eating nutrient-rich foods covering all of the following major food groups in the amounts recommended by your dietician or health care practitioner:

  • Complex (starchy) carbohydrates. These include bread, cereals, potatoes, rice, and pasta which are digested slowly and steadily release energy without causing sharp spikes in blood sugar levels. 
  • Proteins. Choose from lean meats, poultry, seafood, and eggs. Vegetarian sources of protein include beans, peas, lentils, nuts, seeds, and soy products.
  • Milk and dairy foods. Choose from milk, yogurt, and cheese, or fortified soy beverages and yogurt as alternatives for your cystic fibrosis meal plan. ‌
  • Fruit and vegetables. Aim to eat a variety of fruits and vegetables as part of your diet as these are excellent sources of vitamins and minerals as well as fiber, especially in the form of whole foods.  
  • Fats. Oily fish such as salmon, tuna, and sardines are great sources of healthy fats. Choose from healthier vegetable oil options such as sunflower, olive, soy, sesame, and rapeseed oil. Nuts and seeds are also good sources of healthy fats.

The extra calories that you take should always be part of well-balanced meals. Research suggests that people with cystic fibrosis have a tendency to eat more saturated fats which can increase the risk of heart disease. Use more unsaturated fats like the ones found in avocados, nuts, and oils such as walnut and flaxseed oils.