Low fat. Wrong species.
Fat is one of the most important components of a cat's diet. It's the primary energy source, it supports coat condition, and it's essential for absorbing fat-soluble nutrients. The target for an adult cat is around 10% fat in the overall diet.
Muscle meats vary enormously in fat content depending on the species and cut - some are very lean, some sit right in the useful middle range, and others are quite fatty. The practical approach is to mix lean and fattier cuts within the same batch, or alternate between leaner and richer meals across the week. A cat eating persistently below 10% will show it - loss of body condition, a dull coat, and hunger that doesn't resolve despite adequate food volume.
If you need to boost fat, the first choice should always be a fattier raw meat cut. When that's not practical, egg yolk is a useful addition at around 26-30% fat - limit to about a quarter yolk per day per cat. Chicken skin is another whole food option. Rendered duck fat can be used if needed but it's a last resort, not a first move. Whole food fat sources are always preferable.
All figures are approximate and as fed. Always check labels where available, especially on minced meats. And muscle meat alone is not a complete diet - it needs to be paired with a balanced meal completer.
Why low fat is the wrong answer for cats
Low-fat diets for cats come up more than they should. A lot more.
It sounds reasonable on the surface - fat is bad, right? It works for dogs with pancreatitis, so it must apply to cats too.
It doesn't. The consequences of getting this wrong can be serious.
Cats are obligate carnivores. Fat is their primary energy source - not carbs, not protein in isolation. Their entire metabolism is built around it. They also can't convert linoleic acid to arachidonic acid the way dogs can, which means they need it preformed from animal tissue. There's no metabolic workaround.
The minimum dietary fat for an adult cat is around 10%. Kittens, seniors, and cats with CKD often need closer to 15%, because their energy demands are higher or their ability to absorb and utilise nutrients is reduced.
So when a cat is put on a low-fat diet and starts refusing to eat - which happens, because low fat means low palatability for a species that runs on fat - you now have a second problem. Cats that stop eating, even for a few days, are at real risk of hepatic lipidosis. Fatty liver disease. It can develop fast and it can be fatal. The diet prescribed to help can trigger a crisis that's harder to manage than what you started with.
The most common reason vets reach for low-fat dietary advice in cats is pancreatitis. The evidence simply does not support it. Peer-reviewed veterinary nutrition literature is explicit on this - feline pancreatitis is not the same as canine pancreatitis, dietary fat restriction is generally not required, and the priority should be getting adequate calories into the cat, not restricting fat. The low-fat approach for pancreatitis is a dog protocol being applied to a different species.
Is there ever a genuine reason to feed a cat low fat? Yes - one. Hyperlipidemia, specifically hyperchylomicronemia, is a rare fat metabolism disorder where fat restriction is the appropriate treatment. It's diagnosed, it's specific, and it's managed under veterinary supervision. It is not a blanket instruction handed out because something showed up on a blood panel.
If your vet has recommended a low-fat diet for your cat, it's worth asking: what specifically is the diagnosis, what's the evidence for fat restriction in cats with this condition, and how are we going to monitor for adequate intake given the hepatic lipidosis risk?
Those aren't rude questions. They're the right ones.