Up to two-thirds of adults with cystic fibrosis (CF) have used probiotics, and one-fourth still currently use them, according to results of a new study published in the Journal of Human Nutrition and Dietetics. Most of them had not discussed it with their doctor, and one-third were uncertain about its helpfulness.

This cross-sectional study surveyed 205 patients previously diagnosed with CF and 158 otherwise healthy adults assigned to the control group. Out of all individuals with CF, 70% of them admitted to having taken probiotics at some point, and out of these, 24% were currently using them.

Seventy-three percent of probiotic users had not discussed it with their doctors, 33% were unsure about its usefulness, and 21% found them very helpful. Females and patients with university-level educations were more likely to take or have taken them.

Although the control group showed higher probiotic use (80%), these results remain revealing. Both groups claimed to use them for general health, matching probiotics’ habitual marketing. In the CF group, aside from general health, this practice was further motivated by gastrointestinal symptoms and adverse antibiotic effects, which was the key motive in 75% of the participants, followed by immune-related reasons in 45% of the cases.

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Moreover, patients believed probiotics could aid with bloating, antibiotic-associated diarrhea, constipation, and other respiratory conditions, in that order. This study’s high proportion of patients with CF using probiotics highlights the need for additional research regarding its efficacy in treating or preventing symptoms secondary to CF and antibiotic use.

“Implications of the mismatch between the primary reasons reported for probiotic use and the focus of CF research include that there is limited evidence guiding practice for patients or clinicians for using probiotics in the management of CF gastrointestinal issues,” the authors wrote.

“Given the strong patient interest in probiotics yet lack of specific evidence for gastrointestinal symptom improvement, clinicians can assist patients to determine if probiotics have been effective, ideally using a gastrointestinal symptom tool validated for use in the CF population.” Perhaps the most alarming result was the low rate of patients communicating probiotic use with their clinicians.


Anderson J, Tierney A, Miles C, Kotsimbos T, King S. Probiotic use in adults with cystic fibrosis is common and influenced by gastrointestinal health needs: a cross sectional survey study. J Hum Nutr Diet. Published online January 28, 2022. doi:10.1111/jhn.12991