The relationship between nutrition and lung function in CF
Researchers and providers still maintain that the main cause of progression of CF and mortality is loss of lung function. This is often called pulmonary cachexia, which is a fancy way of saying that the lungs lose their ability to function. There is a clear relationship between the lung’s ability to function and an individual’s nutrition status. What is unclear is whether lung deterioration negatively affects nutrition status, or if it is the other way around. Pulmonary function tests (PFTs) have shown that having a body mass index (BMI) in the normal range are associated with better PFT results. One literature review showed that enhanced nutrition and increased caloric intake resulted in not only increased growth in children with CF, but also better lung function. This review also showed that growth hormone therapy does not appear to significantly improve lung function. Another study showed that out of 909 patients with CF the people who were overweight or obese were of a higher age and had better lung function.
Other studies have been done as well. Some have looked at lactobacillus probiotics and claim that they have a positive effect on lung function. Unfortunately these studies were small and therefore unreliable. Consuming more calories than the average person is often recommended with CF. This is because only part of what patients eat is being absorbed. Thus increasing consumption can increase absorption. But what if you’re not hungry? This is why appetite stimulants are also being explored. Small studies are showing that appetite stimulants are increasing BMI and improving lung function, but larger studies need to be done to be sure.