Gum arabic (GA) is a dietary fiber derived from the dried exudates from Acacia Senegal. It has been used in the traditional treatment of patients with chronic kidney disease in Middle Eastern countries. In this study, we explored the effects of gum arabic (GA) on water and electrolyte balance of healthy wild-type 129S1/SvImJ mice (n=18). Feces and urine were collected in metabolic cages before and following 3 or 14 days of treatment with 10% GA in the drinking water. GA enhanced significantly 24h-creatinine clearance (from 108 ± 7 to 147 ± 14 ml/min) but decreased daily urine output (from 1.8 ± 0.2 to 1.2 ± 0.1 ml) and urinary excretion of Na+ (from 226 ± 22 to 196 ± 19 mmol/24h). GA increased fecal Na+ excretion. Urinary ADH excretion increased significantly under GA treatment. GA increased significantly both, intestinal and renal, excretion of Mg2+ and Ca2+ . In contrast, GA decreased urinary Pi excretion from 183 ± 38 to 129 ± 29 mmol/24h. Following GA treatment plasma concentrations of 1,25-dihydroxy vitamin D were decreased. In summary, treatment with GA resulted in moderate but significant increases of glomerular fitration rate and altered electrolyte excretion, effects which may indeed be favourable in patients suffering from renal insufficiency.