Increasing Dietary Potassium Enhances Urine Production and Reduces Risk of Calcium Oxalate Stone Formation in Senior Cats

The objective of these three studies was to determine if dietary potassium supplementation affects urine production or calcium oxalate (CaOx) relative supersaturation (RSS) in adult cats. In the first study, control cats were fed dry food containing 1.08% potassium (as fed), and treatment cats were fed control food supplemented with KCl (1.95% potassium) for 21 days. In study two, cats were fed one of three treatment foods for two weeks in a three-period crossover study design (control food containing 0.84% potassium, and treatment foods containing control food supplemented with KCl at 1.35% or 1.81% potassium). In study three, control and treatment cats were fed similarly to study one, with each experimental period lasting two weeks in a crossover study design. In study one, urine production (p = 0.037), urine potassium excretion (p = 0.049), and urine chloride excretion (p = 0.007) were greater for cats fed test food. In study two, increasing dietary potassium concentration significantly increased water intake and urine production, and decreased USG in a dose–response manner. Urine concentrations of sodium and phosphorus were significantly decreased by urine dilution. In study three, cats consuming test food had a 25% increase in urine production and reduced urine specific gravity compared with cats consuming the control food. In addition, CaOx RSS was reduced (p = 0.007). No adverse effects were observed in healthy cats consuming increased dietary potassium.