Fiber intervention lowers BUN and serum creatinine in chronic kidney disease patients

Blood urea nitrogen (BUN) is quantitatively the most important uremic solute, while serum creatinine is the preferred marker to estimate glomerular filtration rate (eGFR) during routine clinic visits. In a 6‐wk single‐blind, crossover pilot study, we investigated the effects of adding foods fortified with 23 g/d of functional fiber vs low fiber foods to the diets of patients with chronic kidney disease (CKD) (n=13) on BUN and serum creatinine levels. Compliance was 83% for control, and 78% for treatment. Consuming fiber foods decreased mean BUN levels by 9.8%, from 38.5±5.6 to 34.2±5.1 mg/dl (P < 0.05) and serum creatinine by 7.6%, from 2.4±0.3 to 2.2±0.3 mg/dl (P = 0.003). Modification of Diet in Renal Disease (MDRD) eGFR increased 7% from 31.5±3.8 ml/min/1.73m2 to 34.2±4.3 ml/min/1.73m2 (P < 0.05). No changes in body weight, fasting blood glucose, or lipid profile were found. We conclude that high functional fiber intake may reduce serum creatinine and improve eGFR in patients with CKD. Additional studies of longer duration are warranted to confirm this finding and to determine whether these changes are due to improved kidney function. Sponsored by Saskatchewan Pulse Growers.