In many diseases the right food is as much part of treatment as medication. But the “right” food differs from one disease to another, and a mistake can make the condition progress faster. Here are the key principles your vet considers when choosing a diet.
What matters in different diseases
Chronic kidney disease
Less phosphorus, a moderate amount of high-quality protein, omega-3 fatty acids (EPA and DHA) and more water. Potassium is added only if a blood test shows low potassium (more common in cats). Common mistakes: “bananas and potatoes for the kidneys” without a blood test; an ordinary food high in phosphorus.
Heart failure
Sodium restriction depending on the stage, enough calories and protein (to avoid muscle loss), omega-3; for cats, taurine in the food. Common mistakes: cutting protein; salty treats, cheese, sausages and stock.
Chronic hepatitis
Enough protein and calories; less copper in copper-associated hepatitis. Common mistakes: restricting protein without signs of hepatic encephalopathy.
Pancreatitis in dogs
A low-fat food in small, frequent meals. Common mistakes: fatty meat and table scraps.
Food allergy
An elimination diet for at least 8 weeks: a hydrolysed-protein or novel-protein food – and nothing else. Common mistakes: a blood “food allergy test” instead of a diet trial (it is unreliable); treats during the trial.
Diabetes
Cats: a high-protein, low-carbohydrate food. Dogs: the same food at the same times every day, ideally high in fibre. Meals are coordinated with insulin injections. Common mistakes: changing the food or feeding times without talking to your vet.
Bladder stones
The diet depends on the type of stone: struvite stones can be dissolved with a therapeutic food, oxalate stones cannot. More water (wet food). Common mistakes: a “urinary” food without analysing the stone.
Obesity
A weight-loss therapeutic food, a calculated daily amount and gradual weight loss (about 1–2% a week in dogs, more slowly in cats). Common mistakes: sharply cutting the portion of the usual food – this causes nutrient deficiencies, and in cats a risk of hepatic lipidosis.
Why not a recipe from the internet
Studies of home-made diet recipes from books and websites found that almost all of them lacked at least one essential nutrient – most often calcium, vitamin D, zinc and choline, and for cats also taurine. In a sick animal, a mistake matters even more. A home-made diet is possible, but it should be formulated by a veterinary nutritionist.
How to do it right
- First, an accurate diagnosis and the stage of the disease.
- A therapeutic food prescribed by your vet – or a home-made diet formulated by a veterinary nutritionist.
- Switch gradually over 7–10 days (unless your vet says otherwise).
- Do not mix the therapeutic food with other foods or “dilute” it with treats.
- Weight checks and blood tests on the schedule your vet sets.
When to see a vet urgently
- your cat has not eaten for more than a day;
- repeated vomiting or bloody diarrhoea;
- a male cat keeps going to the litter tray without passing urine;
- breathlessness, collapse or sudden weakness.
Sources
- IRIS – International Renal Interest Society: Treatment Recommendations for CKD in Dogs and Cats, 2023.
- Keene B. W. et al. ACVIM consensus guidelines for the diagnosis and treatment of myxomatous mitral valve disease in dogs. J Vet Intern Med, 2019.
- Webster C. R. L. et al. ACVIM consensus statement on the diagnosis and treatment of chronic hepatitis in dogs. J Vet Intern Med, 2019.
- Lulich J. P. et al. ACVIM Small Animal Consensus Recommendations on the Treatment and Prevention of Uroliths in Dogs and Cats. J Vet Intern Med, 2016.
- Stockman J. et al. Evaluation of recipes of home-prepared maintenance diets for dogs. JAVMA, 2013.
- Wilson S. A. et al. Evaluation of the nutritional adequacy of recipes for home-prepared maintenance diets for cats. JAVMA, 2019.
Paw4care editorial team
