Pea hull fiber supplementation does not modulate uremic metabolites in adults receiving hemodialysis: a randomized, double-blind, controlled trial

This was a randomized, double-blind, controlled crossover study in adults receiving hemodialysis. Participants consumed muffins with added pea hull fiber (15 g/d) and control muffins daily for 4 weeks each, separated by a 4-week washout. The intervention contributed an additional 9 g/d of dietary fiber. The central result was that no significant changes from baseline were observed in serum levels of the targeted uremic molecules (p-cresyl sulfate, indoxyl sulfate, phenylacetylglutamine, or trimethylamine N-oxide). Furthermore, supplementation did not modulate the relative abundance of specific health-enhancing gut bacterial taxa. Using machine learning, some microbiota differences were detected between periods, but the primary clinical endpoints were unchanged. The findings suggest that pea hull fiber supplementation at the dose tested does not mitigate serum uremic metabolite levels in this population.