Oxalates are naturally occurring compounds found in certain plants (spinach, beet greens, rhubarb) that bind to calcium and other minerals, reducing their absorption and potentially contributing to calcium oxalate urinary stone formation. Calcium oxalate uroliths are the most common type of urinary stone in cats, and their incidence has been increasing over the past two decades. While dietary oxalate from the small amount of vegetables a cat might eat is a minor contributor compared to metabolic oxalate production, it is worth understanding for owners who offer plant-based treats or supplements.
Your cat's primary oxalate exposure comes from metabolic production rather than diet, since cats eat very little plant matter. If you offer vegetable treats, choose low-oxalate options like pumpkin, zucchini, and green beans over high-oxalate choices like spinach. Keeping your cat well-hydrated is the most effective strategy for reducing urinary stone risk.
Oxalates are not nutrients and have no deficiency. Their absence from the diet is desirable.
High oxalate intake can reduce calcium absorption and contribute to calcium oxalate urinary stone formation in susceptible cats. Cats with a history of oxalate uroliths should avoid high-oxalate foods like spinach and beet greens.
Dietary oxalates bind to calcium in the gut, reducing calcium absorption and potentially forming calcium oxalate urinary crystals. High-oxalate foods like spinach make their calcium essentially unavailable to your cat's body.
What this means: Avoid feeding high-oxalate vegetables (spinach, beet greens) to cats with a history of calcium oxalate urinary stones. Choose low-oxalate options like pumpkin instead, and ensure adequate hydration to dilute urine.
