Senior cat food for low muscle mass

Your vet has flagged something really worth acting on — low muscle mass in senior cats is common but absolutely addressable through diet. As cats age, they actually need more protein than younger adults, not less, and that protein needs to come from real animal meat rather than plant sources to be properly usable. They also benefit from reduced phosphorus to protect the kidneys, and wet food helps keep them hydrated. Before I point you toward something specific — how old is your Selkirk Rex exactly, are there any other health conditions beyond the muscle loss, and what are you currently feeding them?

That dry supermarket food is almost certainly part of the problem. Own-brand senior dry foods tend to be low in actual meat content and high in cereals and plant protein, which older cats can't convert into muscle efficiently at all. Switching to a high-quality wet food will do two things at once — give her the bioavailable animal protein she needs to rebuild lean tissue, and improve her hydration, which dry food just doesn't support. Has she got any issues with her teeth or eating, or is she a good eater generally?

That's reassuring — a good appetite means she'll likely take to a new food well. The issue isn't how much she's eating, it's the quality of protein she's getting. I'd point you toward Animonda Carny Adult — it's a German wet food with a very high real meat content, typically 70–80% meat and offal with no cereal fillers. It's not marketed as 'senior' specifically, but that's actually fine — the senior labelling on cat food is often a marketing gimmick, and what matters is the ingredient quality. The protein is highly digestible animal protein, which is exactly what your vet is asking for. It comes in a good variety of flavours so you can find what she prefers, and it's well within a sensible price range on Amazon UK.

It's a smart thing to think about. At 12, kidney function is worth keeping an eye on even if there's no diagnosis yet — reduced phosphorus is a sensible precaution. Animonda Carny is reasonably moderate on phosphorus compared to many budget foods because the meat content is cleaner and less reliant on bone meal, which drives phosphorus up. That said, if you want to be especially cautious, ask your vet about an annual kidney blood panel — it's a simple check and gives you early warning. For now, moving her off the dry cereal-heavy food will already be a significant improvement for both her muscles and her kidneys.

Go slowly — about ten days is ideal. Start by mixing a small amount of the Animonda Carny in with her current food, maybe 20% new and 80% old for the first few days, then gradually shift the ratio. Cats can be resistant to change, especially older ones, but since she's a good eater you should be fine. If she gets loose stools at any point, just slow the transition down a little. Once she's fully on the wet food, aim for two meals a day and remove uneaten food after 30 minutes — wet food doesn't sit well at room temperature for long.