Urine pH in Cats: What it Means About Their Health
Reviewed by Nelva J. BryantReviewed by Nelva J. Bryant
A cat's urine pH is a measurement that reflects the health of their urinary tract. If the pH is too high or low, cats may develop urinary crystals or stones. A cat's diet and health status can influence their urine pH. Here's the desired range of feline urine pH and how these numbers correlate to a cat's urinary tract health.
What is the Significance of Urine pH in Cats?
The pH levels in cat urine can mean the difference between health and illness. The pH is a measure of acidity or alkalinity in any substance. On the pH scale, 7 is neutral. Values below 7 are acidic while those above 7 are alkaline.
Cats are especially vulnerable to urine pH problems. When pH is too high or too low, crystals can form in a cat's urine. Crystals can combine with other materials in the urine to form grit and stones that cause irritation, bleeding, and/or blockage. A cat with a blocked urethra (the tube that drains urine from the body) will die without rapid treatment.
Urine Specific Gravity in Dogs and Cats
Normal Cat Urine pH
The normal, healthy range for a cat's urinary pH is about 6.3 to 6.6, although this may vary under certain circumstances. Cats need acidic urine to maintain urinary tract health. The lower the pH, the more acidic the urine.
High Urine pH
Alkaline urine has a higher pH (greater than 7) and may be caused by urinary tract infections or diet. The urine should be analyzed for the presence of bacteria and white blood cells. A pH above this range can lead to the growth of struvites, or magnesium ammonium phosphate crystals.
Low Urine pH
A pH lower than the normal range may be too acidic. This may be caused by kidney disease or diet. Low urine pH in cats may lead to the formation of calcium oxalate crystals.
How Diet Affects Cat Urine pH
Cat food that is high in animal protein has an acidifying effect on urine while plant-based or dairy-based diets cause higher pH (alkaline urine). Because cat urine should be slightly acidic (and because cats are obligate carnivores) they thrive on diets high in animal protein.
The relationship between diet and urinary tract health is so important that many of the premium cat food manufacturers now produce foods that are specifically designed to promote urinary health. Prescription diets are available for cats who are at especially high risk for crystal and stone formation. Talk to your veterinarian to determine several good dietary choices based on your cat's particular needs.
The 8 Best Cat Foods for Urinary Health in 2024
How to Measure a Cat's Urine pH
Urine pH is one of several measurements assessed when veterinarians interpret a urinalysis. After collecting a urine sample from your cat, a veterinary technician or assistant will place drops of urine on a test reagent strip (sometimes called a 'dipstick'). These strips contain several reagent pads that change color to measure several factors, including pH, protein, glucose, and more.
If your vet wants you to measure urine pH at home, they may recommend a special color-changing litter or litter additive. The vet will show you how to interpret the color changes.
Other Factors That Affect Feline Urinary Tract Health
Excess Concentration of Minerals in Urine
Although for years the generic "ash" content of cat food was blamed for many cat urinary problems, ash is merely the mineral-rich residue left after fully burning a food and doesn't really indicate the kinds of minerals, nor the amounts and types of each, that are present. That said, excesses in certain minerals can increase the risk of crystal formation. For example, foods that are extremely high in magnesium and phosphorus should be avoided in cats that are at risk for struvite crystals while high-calcium foods can be risky when calcium oxalate stones are a concern.
Water Intake
The urinary tract requires sufficient fluids to keep minerals in solution and prevent them from forming crystals. A cat that takes in adequate water will form less concentrated urine and urinate more frequently. For these reasons, many veterinarians recommend feeding cats that are at risk for urinary crystals only wet food and ensuring that they always have access to fresh water.
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Read the original article on The Spruce Pets.