Wet food offers many advantages to owners of diabetic cats, and most cats like it. Photography NorthStar203 | iStock photo

 If your cat is diabetic, pay extra attention to her diet. Management of feline diabetes involves more than providing insulin injections to control blood glucose, and there are important considerations in food selection.

“First is palatability for the cat. If your cat won’t eat a diet you’re trying to feed even though it is a great food for a diabetic cat, it isn’t worth it,” says John Loftus DVM, PhD, DACVIM, Assistant Professor, Section of Small Animal Medicine at the New York State College of Veterinary Medicine at Cornell. That means you may have to compromise on the ideal diet versus what your cat will eat.

Diabetics should ideally have a consistent schedule for eating so that insulin injections can be given at ideal times with respect to feeding. This means no more free access food dishes (grazing) in most cases. Meals should ideally be fed at specific times (twice daily works best for most cats) and the amount of food eaten should be monitored. “There are some types of insulin (e.g., glargine) that may allow for grazing (free feeding) if a cat won’t adjust to meal feeding. For other types of insulin, cats really should be meal fed exclusively,” says Dr. Loftus. The goal for managing a diabetic cat is to establish a regular protocol of feeding and insulin administration.

What to Feed

Dr. Loftus notes that the nutritional content of the food your cat eats is critical. “The most important thing nutrient-wise in a feline diabetic diet is to go low on the carbohydrates. Your veterinarian can help you, and there are some websites that can help you and your veterinarian with diet selection. Our nutrition service at Cornell is available for assistance with some specific choices”. (visit www.vet.cornell.edu/hospitals/services/nutrition).

It’s helpful to feed wet food whenever possible, as dry food is generally higher in carbohydrates, and the higher water content in wet foods can be beneficial to diabetic cats. 

It’s important to note that not all wet cat food is ideal for cats with diabetes, though. Look for ones with the lowest carbohydrates. Avoid gravy in wet foods, too, as they are usually high in carbs.“The prescription diet Purina DM is an example of a good choice. There are plenty of over-the-counter choices too. Many Friskies or Fancy Feast choices are appropriate. Blue Buffalo’s Carnivora line is also very low in carbs,” explains Dr. Loftus.

According to the Feline Nutrition Foundation (www.feline-nutrition.org), to find the carbohydrate amounts in any type of food: “Add the percentages listed on the label for protein, fat, fiber, moisture and ash. Ignore the other listed amounts, as these will be for minerals included in the ash percentage or be so small as to not affect the calculation. Subtract this number from 100 to get the carb percentage on a wet matter basis.”

While calculating the carb percentage is useful, research has not yet determined an exact figure for “high carb” and “low carb” levels for diabetic cats. Currently available research suggests that 12% or less of energy derived from carbs is a good ballpark estimate. Remember that diseases like liver or kidney problems may influence food choices as well. Consulting your veterinarian who knows your cat’s history is important in making food selections.

Dietary fiber can level out blood glucose levels to a certain extent, minimizing extreme highs and lows, so fiber is an important consideration in choosing a diet for diabetic cat. In addition, fiber can help with weight loss for the overweight diabetic cat by making him feel “fuller”. Since obesity is associated with a decreased response to insulin, attaining and maintaining a healthy body weight is a very important aspect of managing this disease.

All cats should eat top quality protein sourced from meat (cats cannot survive on a vegetarian diet), and since diabetic cats can lose muscle mass, this is a very important consideration for them. Since protein restriction is an important aspect of managing feline kidney disease,  managing coexisting diabetes and kidney disease in cats requires walking a fine line to balance the nutritional needs for these two common problems.

Keep It Simple

Once you have a diet that seems to be working, don’t rock the boat. Even changing flavors or brands with the same flavor can mean different nutritional content. This is not the time to experiment.

It is possible for some diabetic cats to be maintained with just diet once they have been stabilized with insulin therapy. Dr.  Loftus emphasizes, however, that this is not achievable in many cats. “It is important to know that the best predictor of remission is good glycemic (blood sugar/glucose) control. This is best achieved with insulin in most diabetic cats. However, cats that go into remission are probably more likely to stay in remission if they are on a good diet for diabetes mellitus. Cats that are pre-diabetic or ‘mildly’ diabetic may be ok with diet changes alone at first, and if they don’t respond well then you need to add insulin.”

Many cats will need lifelong insulin once they develop diabetes. Even so, a proper diet can keep  required insulin amounts to a minimum and reduce the likelihood of a hypoglycemic (low blood glucose) crisis.

Diabetic cats need a regular health plan to control their illness. Periodic blood glucose curves that require a day in the hospital for serial blood tests can help to verify the true glycemic status of your cat. Owners can also monitor their cat for glucose in the urine at home (normal cats do not have glucose in their urine, and high blood glucose can cause “spillage” of glucose into the urine) using testing strips that can be provided by their veterinarian. Periodic urine cultures can catch urine infections early on, since bacteria tend to grow more easily in urine that contains glucose.

You Can Do It

Having a cat with diabetes requires effort on the part of the owner, but with proper education, planning, and support, diabetic cats can be effectively managed and can live full, active lives. Diet is a critical part of this management, so don’t hesitate to consult your veterinarian or ask for a referral to a board-certified nutritionist for assistance with this aspect of health care for your diabetic cat.

Although there’s no cure for feline diabetes, this disease is manageable with proper diet and medications. Cats with well-controlled diabetes can live for many years with a high quality of life, but owners must be vigilant. 


Low Blood Sugar

If you suspect your cat is having a hypoglycemic (inappropriately low blood glucose) crisis, immediately put some honey or corn syrup on her gums and repeat this as needed until improvement is observed while you contact your veterinarian.  Most hypoglycemic cats will respond fairly quickly to this emergency measure, but it is still important to get her to your veterinary clinic or an emergency service as quickly as you can.

  • Symptoms of hypoglycemia include:
  • Changes in appetite (loss of appetite or increased hunger)
  • Disorientation
  • Weakness
  • Anxiety

Did You Know?

In type I diabetes, glucose concentrations are high because of a decrease in the production of insulin. In type II diabetes, glucose levels are high because cells in the body do not respond appropriately to insulin. Cats with diabetes most commonly suffer from type II diabetes