Calvo-Lerma J, Roca M, Boon M, et al. - Researchers intended to determine if there is a connection between faecal pH (as intestinal pH surrogate) and coefficient of fat absorption (CFA). In addition, faecal free fatty acids (FFAs) have been quantified to determine the amount of digested, but unabsorbed fat. In a 24-h pilot study, individuals with cystic fibrosis followed a standardised diet with fixed pancreatic enzyme replacement therapy doses, corresponding to theoretical optimal doses determined by an in vitro digestion model. Median faecal pH and CFA in 43 patients were 6.1% and 90%, and they were positively correlated. An inverse link was observed between faecal pH and total fat excretion, as well as total FFA. Findings suggested an association of higher faecal pH with longer intestinal transit time and the use of proton pump inhibitors. Although the clinical significance of faecal pH is not fully established, further consideration should be given to its usefulness as a surrogate biomarker for intestinal pH.