You want to switch to a different food. Maybe because your cat is getting older, because your vet recommends it, or because her usual brand is no longer available. Whatever the reason: don't do it overnight. Cats are true creatures of habit. A sudden switch can upset their stomach and gut, and some cats simply leave the new food untouched.
With a calm transition over 7 to 10 days, you give her body time to adjust. And along the way, you see straight away whether it's going well.
The basic schedule: 7 to 10 days
- Days 1–2: about a quarter new food, three quarters old food.
- Days 3–4: half new, half old.
- Days 5–6: three quarters new, a quarter old.
- From day 7: new food only.
Does your cat have a sensitive stomach, or is she a very picky eater? Then feel free to take two weeks. There's no rush: a slower transition is almost always better than one that's too fast.
What you can calmly observe each day
Look at the same things every day, at roughly the same time. That way you can really compare the days.
- Appetite — does she finish her portion, or leave more than usual?
- Drinking — is she drinking about as much as usual?
- Stool — shape, colour and how often. Slightly softer stool at the start is fairly common, but it should soon return to normal.
- Energy and behaviour — does she play and respond as she always does?
Write it down straight away, in a few words. Otherwise, after three days you really won't remember when something started.
Not going so well? Slow down
Is her stool getting softer, or is she clearly leaving more food? Then go back to the previous step of the schedule and stay there for two or three extra days. Once things are fine again, carry on calmly. Slowing down isn't failing: it's exactly how a good transition works.
When should you call your vet?
Don't wait — contact your vet straight away if your cat:
- eats nothing for more than 24 hours;
- vomits several times, or has diarrhoea that doesn't improve quickly;
- has blood in her vomit or stool;
- is lethargic or hiding;
- has trouble urinating, or keeps going to the litter box without producing anything.
In doubt? Better to call once too often than once too few.
Is your cat still a kitten, getting on in years, or on a special diet for a medical reason? Then talk to your vet first before you change anything about her food.
Keep track — so you don't have to guess
The PawFix Cat Care System is made for exactly these moments. First you record your cat's baseline in a start profile. Then you follow her for fourteen days with the same short routine — Do, Look, Note, Decide — and make one clear decision each day: go ahead, slow down, observe or call your vet.
Want to see how it works first? Download 2 real pages for free, no sign-up needed.
PawFix supports structured observation and does not replace a diagnosis or a vet's advice. If you're worried about your cat, contact your vet.