Senior Birman needs more moisture — vet advice

A 13-year-old Birman on dry food only with a vet telling you to increase moisture — that's a situation that needs addressing quickly. Cats are obligate carnivores with specific nutritional requirements many commercial foods don't fully meet, and dry food is particularly problematic for long-term kidney health because cats have a naturally low thirst drive and simply don't compensate well for the missing moisture. At 13, a Birman's kidneys are already under age-related pressure, so this is genuinely important. Can you tell me a bit more — does your cat have a confirmed kidney issue, or is the vet being proactive? And is she eating the dry food well, or are there any pickiness or appetite concerns?

That's actually a good position to be in — catching it at the early stage means diet changes can genuinely slow progression. The slightly elevated values tell me her kidneys are working harder than they should, and increasing moisture through food is one of the most effective ways to reduce that load. The other thing that matters at this stage is phosphorus — kidneys struggle to process it, and most standard cat foods, wet or dry, contain more than an early-CKD cat needs. So you want wet food specifically formulated for renal support, not just any wet food. Is she indoor-only, and roughly what's her weight?

Perfect weight for a Birman, and indoor-only means her calorie needs are modest — that all works in your favour. My recommendation is Royal Canin Veterinary Diet Renal wet cat food in the pouches. It's specifically formulated for cats with kidney disease or early kidney decline — low phosphorus, controlled protein quality, and critically it has around 75–80% moisture content, which is exactly what her kidneys need. Royal Canin's renal range is one of the most rigorously tested available in the UK, it's palatable to most cats, and because your Birman isn't picky, the transition should be straightforward. Start by mixing a small amount alongside her dry food for a few days, then gradually shift the ratio until she's on wet-only or wet-primary. You can keep a small amount of the renal dry version as a top-up if needed, but the wet should become the foundation of her diet. It's available on Amazon UK and your vet may also stock it.

For a cat with early CKD, getting as much moisture through food as possible is the priority, so wet food should make up the bulk of her diet — ideally 80–90% of what she eats. A small amount of the Royal Canin Renal dry food is fine as a supplement if she seems to want something to crunch, but I'd avoid her previous standard dry food because the phosphorus levels won't be controlled. The key rule: if it's dry, it should be the renal-specific version, not a general adult or senior kibble. The wet renal pouches twice a day with a light scatter of renal dry if she needs it is a perfectly sensible routine for a cat at her stage.

Good call — and well done for acting on it early. One last thing worth knowing: recheck bloodwork in around 8–12 weeks once she's fully transitioned. If her kidney values stabilise or improve, that's confirmation the diet is doing its job. Keep fresh water available in multiple spots too — cats with kidney issues benefit from having water sources dotted around the home, and some do better with a cat water fountain if she ignores still water. Your vet gave you good advice; this diet change is the single most impactful thing you can do for her right now.