Obesity and Diabetes in Cats: The Disease You Can Often Reverse

Here is the short version: most cats in this country are now overweight, and carrying extra weight is the biggest reason cats get diabetes. That sounds like bad news, and partly it is, but it comes with a genuinely hopeful twist that the canine version of this story does not have. Feline diabetes is often reversible. With the right diet, weight loss, and early treatment, a real share of diabetic cats stop needing insulin altogether. This guide explains how weight and diabetes are linked in cats, why remission is possible, and exactly what to do about it.

Most cats are carrying too much

This is not a niche problem. By veterinarians' own assessment, about 61 percent of cats in the United States are overweight or obese.¹ And as with dogs, owners tend not to see it on their own pet. In the same survey, more than a quarter of owners whose cats were judged overweight by a vet described those cats as normal, ideal, or thin.¹ A slightly round cat has quietly become most people's mental picture of a normal cat.

~61%

Association for Pet Obesity Prevention, 2022

Why fat drives diabetes in cats specifically

Feline diabetes is mostly the type-2-like form, built on insulin resistance plus a tiring-out of the cells that make insulin.² That mechanism is exquisitely sensitive to body fat. The more excess fat a cat carries, the more its tissues resist insulin, and the harder its pancreas has to work to keep blood sugar in check. Push that system long enough and it fails. A classic study found that heavy or obese cats were about four times as likely to develop diabetes as cats at an optimal weight.³ Cornell states the same figure in plain terms: obese cats are up to four times more likely to become diabetic.²

~4×

Scarlett & Donoghue, JAVMA 1998; Cornell Feline Health Center

This is worth pausing on, because it is a real difference between species. In dogs, obesity is not considered a primary cause of diabetes, a point we make in our dog obesity and lifespan guide. In cats, the link is central. That is what makes weight the most powerful lever an owner has over feline diabetes, in both directions.

How common diabetes is, and who gets it

Diabetes itself affects somewhere between roughly 1 in 100 and 1 in 500 cats.² Beyond weight, the risk factors cluster in a recognizable cat: older, male, neutered, indoor and inactive, and sometimes on steroids for another condition.²⁴ Breed plays a role too. Burmese cats are clearly predisposed in Australia, New Zealand, and parts of Europe, where one study found diabetes about three times more common in Burmese than in cats overall.⁸ That breed pattern may be weaker in the United States, so it is a regional signal rather than a universal one.

The signs worth knowing

Diabetes tends to give itself away through thirst and the litter box. The most common early signs are increased drinking and urination, paired with weight loss even though the cat is eating well or even more.² A cat that is suddenly emptying the water bowl and producing large, heavy clumps in the litter deserves a blood and urine test. In more advanced cases, a cat may start walking with its hocks dropped low toward the ground, a flat-footed "plantigrade" stance caused by diabetic nerve damage. It looks alarming, it is generally not painful, and it often improves once the diabetes is controlled.²

The hopeful part: remission

Here is what sets feline diabetes apart from the human and canine versions. Cats can go into remission, returning to normal blood sugar without insulin, and a meaningful fraction do. The key is acting early and controlling blood sugar tightly. In a landmark study using a low-carbohydrate diet and home glucose monitoring, overall remission reached 64 percent, and it climbed to 84 percent when intensive treatment began within six months of diagnosis, versus 35 percent when it started later.⁵ Diet matters on its own, too: cats on a low-carbohydrate diet were more likely to come off insulin than cats on a higher-carbohydrate, higher-fiber diet.⁶

up to 84%

Roomp & Rand, J Feline Med Surg, 2009

Cornell adds the honest counterweight to that optimism: if a cat has not gone into remission within roughly the first six months, it will most likely need insulin for life.² Which is precisely why the early window is so valuable. The clock on remission starts ticking at diagnosis, so a fast, committed response is not just good care, it is the thing that makes a cure plausible.

A new kind of pill, with a real warning

Treatment has changed recently. For most of its history, feline diabetes meant twice-daily insulin injections. In 2022 and 2023 the FDA approved two oral drugs, bexagliflozin and velagliflozin, from a class called SGLT2 inhibitors, which lower blood sugar by flushing excess glucose out through the urine.⁷ For the right cat, a daily pill or liquid instead of injections is a real quality-of-life improvement.

The warning attached to them is not fine print, and we will not bury it. These drugs are only for otherwise-healthy cats that have not been treated with insulin, and they carry a serious risk of diabetic ketoacidosis, a life-threatening emergency that can develop even when blood sugar looks normal.⁷ That makes careful candidate selection and close monitoring essential. This is a genuine advance, and it is one to use with a vet's full involvement, not a shortcut to fewer vet visits.

Reading your cat's body, and losing weight safely

The tool for staying ahead of all this is the body condition score, a 9-point scale where 4 to 5 is ideal.¹⁰ The checks are simple. You should be able to feel the ribs without pressing through a pad of fat, see a waist when you look down from above, and see the belly tuck up rather than hang from the side. If the ribs are buried and the waist is gone, your cat is overweight, whatever it weighs on paper.

One feline-specific caution matters enormously. Cats must lose weight slowly. A cat that drops weight too fast, or stops eating, can develop hepatic lipidosis, a dangerous fatty-liver condition, so weight loss should always be gradual and vet-guided.² Never crash-diet a cat. The current feline diabetes guidelines emphasize the same combination that drives remission: weight management, increased activity, and an appropriate diet, with low-carbohydrate options favored for diabetic cats.⁹

What to do this week

1. Run the hands-on body condition check, ribs, waist, and belly tuck, and be honest about what you find.
2. If your cat is drinking and urinating more, or losing weight while eating well, ask your vet for a diabetes screen now, while the remission window is open.
3. Measure meals instead of free-feeding, and talk to your vet about a target weight and, for a diabetic cat, a low-carbohydrate diet.
4. Add daily play and activity, and plan any weight loss slowly with your vet to protect the liver.

Feline diabetes is one of the few serious diseases on this site where the word "reversible" honestly belongs. The same thing that causes it, excess weight, is the thing you can change, and the cats whose owners act fast and feed them right are the ones who most often come off insulin for good. The bowl and the clock are both in your hands.