What's a Good Food for a Cat With Struvite Crystals?

Woman kissing cats head
Rafael Elias/Getty Images

A reader asks: "My sister's cat has struvite crystals. The vet recommended Hills and Waltham S/O foods. My sister's cat doesn't quite like the taste of these foods (he was on Wellness) and my sister doesn't like the fact that they use chicken by-products in their foods. Does anyone have any recommendations of brands and foods that she can give him?"

What Are Struvite Crystals?

Struvite crystals are urinary tract stones and ​struvite is a material that is composed of magnesium, ammonium and phosphate.

Stones can have various shapes and sizes, and when they block the urinary tract, they can quickly lead to kidney failure and become life threatening. Immediate veterinary care is critical for diagnosis and removal. Signs of stones to watch out for include:

  • Frequent use of the litter box
  • Urinating outside the litter box around the home
  • Straining to urinate; painful urination accompanied by crying sounds
  • Excessive licking of the urethral area
  • Bloody urine
  • Inappetance
  • Depression

Why Struvite Crystals Form

The actual reasons why cat crystals is not well understood, but cats can be predisposed to stones because of:

  • Low water intake
  • An inflammation in the lower urinary tract
  • A high pH in the urine (alkaline environment)

The cause of struvite crystals in cats is most often the result of eating dry cat food. Due to the lack of moisture in the diet, the urine becomes too concentrated and highly alkaline.

Most often, dry commercial cat foods contributes to the development of struvite crystals.

Because of the lack of moisture in kibble, cats get dehydrated, the urine becomes too concentrated, and plant-based ingredients in dry food causes the urine to become too alkaline. The combination of alkalinic and concentrated urine makes cats prone to forming struvites. To eliminate struvite crystals, the goal is to create a more acidic and diluted  urine.

However, cats do not drink water naturally, as they've evolved over millenium to get most of their moisture from prey.  Using prescription diets to make the urine more acidic often does not work because most cats find the foods unappetizing. The best line of defense (and prevention) is a balanced raw meat diet that should help eliminate struvite crystals and prevent them from recurring.  This will encourage a more natural pH in the urine, and the water content of raw meat (usually containing 75 – 80 percent moisture) creates a more dilute urine that's not conducive to the formation of struvites.

Tips to Prevent Recurrence of Struvite Crystals

Her are some additional easy tips to help prevent struvite crystals from recurring:

  1. Feed small meals frequently which will help reduce fluctuation in urine pH.
  2. Provide fresh water places in multiple water dishes in different places. Also try a fountain to pique your cat's interest. You can also offer chicken broth to encourage your cat to drink more.
  3. Provide a sufficient number of litter boxes placed in quiet areas.
  4. Decrease stress by reducing major changes in routine.