They changed his food's recipe and now he won't touch it. Day 3 of the standoff

Oscar has eaten the same chicken wet food for four years. The brand did one of those "new improved recipe!" relaunches, new packaging, and he took one sniff of the first new pouch and looked at me like I'd served him a dishcloth.

That was Wednesday. It's now Saturday. He's had maybe a third of his normal amount over the three days, some biscuits, a bit of licked gravy, plus whatever he's guilt-tripping out of my neighbour, which I can't quantify. I've tried two other brands, warmed it, added the water from tuna. He sits by the bowl and cries at me, which is somehow worse than ignoring it.

He's 6, indoor, a bit on the chunky side which google is now telling me is its own problem with cats not eating?? How long do I let a healthy-ish cat hold out before this stops being fussiness?

The recipe change fury is real, we lost a year of feeding peace to a "new improved" once. Two practical things that worked here. First, see if any shops or sellers still have old-recipe stock, the date codes give it away, buying a month of the old stuff lets you do a SLOW mix instead of a cold switch. Second, the mixing itself: start at something like 80% old and 20% new and shift the ratio over a week or two. Going gradually was the whole game with mine, every shortcut restarted the sulk.

The general feeding advice above is sound, but I want to flag the part of your post that matters most clinically: an overweight cat eating well below normal for several days is not a behaviour problem to wait out. Cats, especially carrying extra weight, can develop serious liver trouble surprisingly quickly when their intake drops, and "a third of normal for three days and counting" is at the point where I'd want a vet's eyes on the actual cat rather than a forum's guess about the actual cat. Partly to protect against that, and partly because appetite changes sometimes get blamed on the new recipe when something else started the same week.

If the clinic confirms he's simply outraged rather than unwell, then the slow-mix approach two_tabbies describes is exactly what we suggest, and the site's guides on when a cat needs the vet and wet versus dry food cover both halves of this: the warning signs, and how to run a food transition without a standoff.

Not a diagnosis of Oscar from here, just the honest general line: fussy is a negotiation, barely eating is an appointment.

Coming back to say thank you and confess. Took him in Tuesday. Physically fine, vet's verdict was essentially "this cat is extremely cross and slightly too round," but she was really clear she'd rather see ten outraged Oscars than one late liver case, so no regrets about going. Found six trays of old-recipe stock at a pet shop two towns over (the things we do), mixing it 75/25 as prescribed by this thread. He's eating. Still giving me the dishcloth look first, on principle.