Roughly 60% of pet cats in developed countries are overweight or obese, and the percentage is climbing. Most owners can't see it because the comparison is "other cats in the neighborhood," who are also too heavy. Excess weight quietly causes diabetes, arthritis, fatty liver disease, urinary problems, and a shorter life. The good news: it's reversible, and the method is straightforward.
How to tell if your cat is overweight
Forget the scale for a moment. Use your hands.
Body condition check:
- Run a hand along the ribs. You should feel each rib with light pressure, like running your fingers over the back of your hand. Pressing hard to find them means too much fat.
- Look from above. A cat at a healthy weight has a visible waist behind the ribs. A straight line from shoulder to hip (or worse, a bulge) is overweight.
- Look from the side. A small belly tuck is normal. A swinging abdominal pouch means obesity. (Note: a small loose flap of skin in front of the back legs, the "primordial pouch," is normal in all cats, even thin ones. Don't confuse it with fat.)
The scale matters too. Most domestic shorthair cats land between 3.5 and 5 kg at a healthy weight. A jump from 4 kg to 5 kg sounds small. It's 25% body weight. For a 70 kg person, the equivalent of gaining 18 kg.
If you're not sure, ask your vet at the next visit for a body condition score. They'll rate your cat from 1 (emaciated) to 9 (obese). Anything above 6 needs intervention.
Why crash dieting is dangerous
Cats can develop hepatic lipidosis (fatty liver disease) within a few days of not eating enough. The body mobilizes fat to the liver faster than the liver can process it. The condition is potentially fatal and requires aggressive treatment. I knew a cat who skipped two days of food during a house move and ended up in the ICU on feeding tubes for ten days. He recovered. The bill didn't.
What this means in practice:
- Never starve a cat. Even a day or two of refused food in an overweight cat is dangerous.
- Don't cut calories more than 20% below maintenance without vet supervision.
- Target slow weight loss: 0.5–2% of body weight per week. For a 6 kg cat, that's about 30–120 grams per week. The slow end is safer.
- Weigh weekly, on the same scale, at the same time of day.
The whole process for a cat with a kilogram to lose typically takes 6–12 months. There is no honest shortcut.
The diet plan
Step 1: Calculate target calories. Start with the maintenance calories for your cat's target weight, not current. A rough formula:
- Maintenance kcal/day ≈ 30 × (target weight in kg) + 70
For a cat whose target weight is 4 kg: 30 × 4 + 70 = 190 kcal/day.
Feed roughly 80–90% of that. For our example: 150–170 kcal/day.
Step 2: Switch to wet food, or mostly wet. Wet food has fewer calories per gram and more water, so the cat feels full on a smaller calorie count. A dry-food-only cat on a diet often feels hungry constantly. The same calories in wet food rarely cause that.
Step 3: Measure every meal. A kitchen scale or a labeled measuring cup. "About a handful" is how cats stay fat.
Step 4: Feed 3–4 small meals, not 2 large ones. Smaller, more frequent meals keep hunger manageable and prevent the overnight fasting that triggers fat metabolism issues.
Step 5: Cut treats hard. Treats are usually 10–25% of an overweight cat's intake. Either stop them entirely or use kibble from the daily allowance as "treats."
A purpose-built diet, if needed
For cats with a lot to lose or for those who plateau, ask your vet about a prescription weight-loss diet. These are calorie-restricted but bulked up with fiber so the cat still feels full. They're more expensive than regular food but cheaper than treating diabetes for years.
Activity ideas that actually work for cats
Cats don't go for walks. They will hunt. The goal is short bursts of high-intensity play, twice a day.
- Wand toys with feathers or fabric on the end. Move them like prey. Quick darts, pauses, hide behind furniture. Let the cat catch the toy at the end so the hunt feels complete.
- Puzzle feeders and treat balls. Make the cat work for some of the daily kibble. Start easy, increase difficulty.
- Stairs. If you have them, throw a toy or kibble piece up or down. Cats will chase.
- Climbing furniture. A tall cat tree near a window adds vertical activity that flat space can't.
- A second cat, if your household and budget can absorb it, is often the single biggest activity booster for a bored solo cat.
Aim for two 10–15 minute play sessions a day. Most cats won't keep going much past that. When they walk away, they're done.
What success looks like
A successful weight loss plan is boring. Weekly weigh-ins show slow steady drops, food is measured, treats are tracked, and the cat plays more easily without panting. After six months you'll feel ribs you couldn't find. Keep going until the body condition is right, then adjust portions upward slightly for maintenance, usually about 10% more than the weight-loss amount.
Don't go back to the old feeding habits. They're what got you here.