Science Update

New study demonstrates the benefits of resistant starch in patients with chronic kidney disease

Over 10% of the adult population suffer from chronic kidney disease (CKD). While the two leading underlying causes of end-stage kidney disease are type II diabetes and hypertension, there can also be a dysbiosis of the gut microbiome, along with inflammation and oxidative stress as well. In addition, environmental toxins and proton pump inhibitor (PPI) use have also been linked to CKD.

Previous research has demonstrated that a high fiber diet can mitigate disease severity and kidney dysfunction in patients with CKD. Now, in a new study published in Nutrition & Metabolism, researchers demonstrated the benefit of resistant starch (RS) with CKD.

A high fiber diet leads to the production of short chain fatty acids (SCFAs) in the gastrointestinal tract. These play an essential role in T regulatory cell activation, which regulates the intestinal immune system. If there is dysregulation in the immune system, there can be increased inflammation seen in CKD.

This new study was a double-blind randomized clinical trial consisting of 50 patients in end-stage renal disease. Half of the patients were given a resistant starch-enriched diet while the other half was given a placebo diet over an 8-week period.  Those receiving the resistant starch-enriched diet were given crackers with 20 g of RS for the first 4 weeks, which was increased to 25 g for the remainder of the study. Laboratory assessments of BUN, creatinine, uric acid, hemoglobin, hemocrit, uric acid, hs-CRP, p-cresol, indoxyl sulfate, and bone markers were measured at baseline and at the end of the study.

Results showed a significant reduction of creatinine, uric acid, and p-cresol levels in the resistant starch group. There was not a significant change in the other parameters. There were no side effects, including gastrointestinal intolerance, with the recommended doses of resistant starch. Based on these results as well as the safety of consuming a diet with resistant starch, it makes sense that this a great adjunct in the treatment of chronic kidney disease. Other nutrients to consider include fish oil, phosphatidylcholine, and n-acetyl-cysteine and glutathione.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

Source: Khosroshahi HT, Abedi B, et al. Effects of fermentable high fiber diet supplementation on gut derived and conventional nitrogenous product in patients on maintenance hemodialysis: a randomized controlled trial. Nutr Metab (Lond). 2019 Mar 12;16:18.