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Nutrition Nuggets is the newest offshoot of petMD's Cat Nutrition Center. Each week Dr. Coates will use her expertise and wisdom to blog about the intricacies of cat nutrition.

What Foods Should an Old Cat Eat?

3 min read

April 29, 2016

Our cats are living longer than ever, which leads to the question, “What should old cats eat?”


If we’re talking about cats who are truly nearing the end of their lives, I think the answer is “whatever they want.”


Cats become extremely finicky eaters as their quality of life declines, so I consider it a great success if we can get them to eat anything at all. Before we reach that point, however, there’s a lot owners can do when it comes to finding a healthy cat food for older cats to maximize their cat’s health and longevity. 


A cat’s digestive physiology changes as they gets older. Around the age of 11 or 12, the ability to digest fat starts to decline. Fats contain more calories per gram than do either proteins or carbohydrates, so this can have a major effect on an older cat’s ability to extract calories (energy) from cat food. To make matters worse, research has shown that around 20 percent of cats over the age of 14 have a reduced ability to digest protein. Put these two conditions together and without dietary intervention, a cat will lose both fat and muscle mass. The loss of muscle mass is especially concerning because these individuals are at increased risk of illness and death.


Most older cats also have some degree of arthritis and are at heightened risk for kidney disease. Advanced age also increases the production of free radicals within the body. A free radical is “a group of atoms containing oxygen and electrons that can alter and damage the chemical structure of cells or other compounds.”


Free radicals essentially “steal” electrons from whatever is nearby. When another molecule is forced to give up an electron, it often becomes a free radical itself, which continues the cycle of cellular injury.


Based on all this, the best foods for older cat have the following characteristics:

  • High antioxidant levels (e.g. Vitamins A, C, and E, beta carotene, and selenium) to counteract free radical damage.
  • Low levels of phosphorus to protect the kidneys. High quality protein sources contain less phosphorous than do those of low quality.
  • Enough protein to maintain a cat’s muscle mass. Extra carnitine (an amino acid) can also help in this regard.
  • Fish oils and other sources of essential fatty acids to counteract the effects of brain aging and promote joint health.
  • A moderate to high level of fat, based on a cat’s body condition score. Skinny cats need a lot of fat to maximize their caloric intake. Overweight cats can do with a bit less.
  • And last, but certainly not least, the best food for older cats will have excellent palatability and smell to stimulate the appetite.


These recommendations can certainly change if an older cat suffers from a disease that is managed, at least in part, through diet. Ask your veterinarian to help you determine which particular food for older cats might be best for your cat based on their individual needs.




Dictionary of Veterinary Terms: Vet-speak Deciphered for the Non-Veterinarian. Coates J. Alpine Publications. 2007.



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