Intakes of specific macronutrients are associated with gut microbiota in a group of free-living adults with cystic fibrosis (CF)

![CDATA[Objectives: Dietary components, particularly macronutrients can modulate the gut microbiota (GM) in the general population. The GM appears disrupted and may link with airway events in CF, where lung disease remains the major clinical challenge, accompanied by rise of comorbidities such as gut inflammation and gastrointestinal (GI) malignancy, and potentially increased cardiovascular diseases (CVD) risk, despite improved survival. Accumulating evidence suggests a role of GM in these CF-related comorbidities. The present study explored the associations between dietary macronutrients and GM in free-living adults with CF. Methods: The associations between macronutrient intakes and GM variations based on 16ss rDNA sequencing results of faecal microbiota from 16 adults with CF were tested at a false discovery rate <0.3. Results: Carbohydrate (CHO) and saturated fat (SFA) intakes were associated with unweighted UniFrac distances (both p < 0.05, R2 = 0.078, q = 0.24, adonis). Resistant starch (RS) and alcohol intakes were associated with weighted UniFrac distances (both p ≤ 0.045, R2 ≥ 0.13, q = 0.28, adonis). Intakes of CHO, SFA and RS correlated with families Microcococcaceae, Enterococcaceae and Streptococcaceae, respectively (all p ≤ 0.0032, r ≥ 0.65, q ≤ 0.29). RS intake also correlated with classes Bacilli and Actinobacteria (both p ≤ 0.025, r ≥ 0.56, q = 0.28). Conclusion: Intakes of some macronutrients correlated with gut microbiota variations in this group of adults with CF. These correlations may have implications in management of CF lung disease, GI co-morbidities, and even CVD risks. The therapeutic value of GM modulation by dietary macronutrients in CF management requires more investigation.]]