Eating well, and maintaining a healthy body weight are vital for individuals with Cystic Fibrosis (CF). A good nutritional status has been directly linked to improved lung function, reduced chest infections and ultimately, improved survival rates. However, as many CF patients and their families will know- this task may prove much more difficult than expected.

CF patients experience many limitations which make maintaining a healthy weight difficult, and even in the case of a normal weight, patients may not be eating the correct foods to optimize their nutritional status and overall health. In the case of children, this is particularly problematic as the lack of adequate nutrition may compromise normal growth and development. Nutritional needs of individuals will vary according to age, weight, height, symptoms, lung function and activity level. It is therefore important for CF patients to seek professional advice from a Dietitian who, along with the medical team, will advise the patient on their individual requirements, and work with the patient to deliver practical recommendations, ensuring they are eating what their body needs to stay healthy and strong.

Lets have a closer look at how CF affects the nutritional status of patients.

Undernutrition is a frequent feature of CF, and results from a combination of conditions that increase energy losses, increase energy needs, and lead to inadequate nutrient intake.

  1. Increased energy losses
  • Many CF patients have inadequate levels of digestive enzymes due to pancreatic insufficiency. This leads to impaired absorption of nutrients, especially fat.
  • Other digestive abnormalities which CF patients experience contribute to energy loss. These include intestinal inflammation, impaired insulin secretion and insulin resistance (CF-related Diabetes) as well as liver disease associated with CF.
  • Increased energy needs.
  • Energy needs are higher in people with CF in comparison with the needs of other individuals. This is due to ongoing lung inflammation and infections associated with CF.

2. Inadequate nutrient intake.

  • People with CF, especially children and adolescents, are often unable to consume sufficient energy to overcome energy shortfalls.
  • Psychosocial issues, such as stress and treatment noncompliance, may contribute to energy shortfalls.
  • Gastrointestinal discomfort including reflux, and constipation, as well as side effects of medication can also decrease appetite, and lead to decreased energy intake.

3. Vitamin and Mineral Deficiency.

  • Decreased fat absorption resulting from pancreatic insufficiency can cause people with CF to become deficient in vitamins which require fat for absorption and transport in the body. These include vitamin A, vitamin E, vitamin D and vitamin K.
  • Without adequate sun exposure, CF patients are also at risk of becoming vitamin D deficient.
  • Patients with CF may have higher requirements for salt, calcium, iron, zinc, and selenium. This is linked to the increased sweating, malabsorption, and chronic inflammation associated with CF.

Here are a few top tips for increasing energy intake and meeting calorie requirements:

  1. Aim to consume five to six smaller meals spaced throughout the day rather than three larger meals.
    • Regular meals and snacks improve energy intake in patients struggling with poor appetite.
  2. Meals and snacks should be appetizing in appearance and taste.
    • This has been shown to improve energy intake, particularly in children.
  3. Household ingredients which are high in energy and protein should be added to meals and snacks to increase the energy and protein content without increasing the bulk of the meal.
    • Examples include adding vegetable oil, peanut butter, eggs, or dry milk powder to porridge, soups, gravies, casseroles or milk based drinks.
  4. At least 2 portions of milk or yogurt should be consumed daily to ensure adequate intakes of energy, protein, vitamin D and calcium.
    • Full cream dairy can be consumed to increase calorie intake.
  5. Make use of a suitable nutrition supplement which is high in energy, protein, vitamins and minerals to complement the diet where necessary.
    • Consult your Dietitian or Medical Doctor, for advice on suitable options.

CF and Diabetes


As mentioned above, many CF patients develop pancreatic insufficiency and CF related Diabetes. This creates a further challenge in that in addition to needing to consume sufficient calories to meet requirements, these individuals need to ensure that they are consuming the right amount, and type of food to control their blood sugar levels, preventing rapid increases and decreases that correspond with sugar highs and lows.


Here are a few top tips for maintaining constant blood sugar levels:


  1. Aim to consume 5 – 6 small meals throughout the day.
    • This will ensure that blood sugar levels are kept constant by preventing both overeating at meals, as well as sugar lows between meals.
  2. Carbohydrate-containing foods do not need to be avoided completely!
    • Carbohydrates are an important source of fibre, and several vitamins and minerals.
    • The type and amount of carbohydrates is what is important.
  3. Choose wholegrain carbohydrates.
    • These are high in fibre, which slows the digestion and therefore release of sugar into the blood stream.
    • Examples include whole-wheat bread and pasta, brown rice, oats, quinoa, bulgur wheat and buckwheat.
  4. Replace refined carbohydrates with high fibre alternatives.
    • These include legumes (beans, lentils, split peas, chickpeas) and starchy vegetables (butternut, potato, sweet potato, corn).
  5. Carbohydrates should be split up in meals and snacks throughout the day.
  6. Carbohydrate portions should be controlled- eat one portion of carbohydrates at a time.
    • A rule of thumb for carbohydrate portions is that the carbohydrate on your plate should be about as big as the size of a clenched fist.
    • Some examples include:
      • ½ cup cooked pasta/rice/porridge
      • ½ cup cooked starchy vegetables (potato, sweet potato, corn, peas).
      • 1 medium fruit
      • 1 slice of bread
  1. Eat carbohydrate containing foods with foods high in protein or fat.
    • Eating carbohydrate in combination with protein and fat slows digestion, preventing blood sugar spikes after a meal, keeping sugar levels more constant.
    • Examples include yoghurt with a handful of nuts or seeds, or apple slices with peanut butter.


By Jay Hamaan (read more info about her in the blog)

COVID-19 Portal