Cats are built to eat steadily. An overweight cat who stops eating can become unwell, and the rate of loss that is safe for her is a clinical judgement. That is why the division of labour in this guide is strict: the vet sets the goal weight, the daily amount and the recheck rhythm, and you run the weighing, measuring and household discipline that make those numbers happen between appointments.
Before Anything Changes: the Vet's Plan
Start at the practice, not at the food bin. Ask what she weighs today, what goal the vet is aiming for, exactly how much food per day should take her there, whether treats survive inside that amount and how they are counted, and when the first recheck falls. Ask which foods in the house the plan covers, including dental chews, lickable treats, milk, and anything the children feed her, because a plan built on the main meals alone leaks calories at every edge.
Write the plan in the vet's figures and pin it where every feeder can see it, with the daily amount, meal split and treat rule in plain words; scoops and handfuls drift, grams on a scale do not.
The Weighing Routine
Weigh her weekly, on the same day, at the same point in the day, before a meal rather than after one. A reliable home method is the carrier method: put her in her carrier, weigh carrier and cat together on bathroom scales, then weigh the carrier empty and subtract, recording both figures so the arithmetic can be checked.
Record the figure immediately, dated, and plot it as a line over the weeks. The line is the point: single weigh-ins bounce with water, litter visits and mood, while the trend across four to six weeks shows whether the vet's plan is biting. Expect the line to move gradually. A line falling suddenly, or appetite dropping with it, means ring the practice; a line unmoved by recheck is information for the vet, not a cue to cut food yourself.
Measuring Food and Ending Grazing
Weigh each portion on kitchen scales at the start of the day and set the day's full allowance aside, so every meal and treat comes out of a known pot and nothing is added on top across the evening. Split the allowance into set meals and end the all-day grazing bowl; a cat who can nibble around the clock cannot be portioned, and neither can her intake be reported honestly at recheck. Feed her separately from other cats, behind a door if needed, and lift their bowls between meals.
Treats come out of the allowance, not alongside it. Play and attention become the currency that treats used to be, and every person in the house, plus visitors, works to the same rule; the plan usually fails at the soft-hearted extra, not at the measured meals.
Activity That Suits a Cat
Build movement into the day in her language: two or three short play sessions with a wand toy, spread across the day and ended while she is still interested, a feed moved to the top of the stairs or the far end of the hall if her joints allow, and part of the allowance scattered or hidden in boxes for her to hunt. Keep sessions brief and stop if she breathes heavily or walks away.
Rechecks and Warning Signs
Keep the recheck rhythm the vet set, often a weigh-in every few weeks at first, and bring the weight graph, the food record and your notes on activity and appetite. Ring sooner between rechecks if she refuses food across a day, eats far less for two days, vomits repeatedly, or seems unwell in herself; in a cat reducing weight, not eating is a call-the-vet sign, never a wait-and-see one.
Held against the plan inside KinsLe, her Pet Passport weight history shows the practice a single dated line from the first weigh-in to the latest, with the agreed amounts beside it, so adjustments are made on evidence the whole household can see.