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Dry-Versus-Wet-Food for Cats?

For most cats, the choice is not critical.

[From Tufts June 2012 Issue]

If you compare the “Guaranteed Analysis” on a can of wet cat food to the one on a bag of dry kibble, the dry food would seem the obvious choice because it shows much higher percentages of protein, fat, and fiber. But that’s only because canned food, which contains more water, is more dilute. The nutrients the cat actually ingests in a serving are more dependent on the product than the form in which it’s delivered. “There is no inherent reason to feed canned or dry food other than pet or owner preference,” says Lisa Freeman, DVM, PhD, a veterinary nutritionist at Tufts Cummings School of Veterinary Medicine. What is important is to select a good-quality food manufactured by a well-known, reputable company.

Granted, for cats with lower urinary tract problems, including bladder stones or cystitis, wet food makes a better choice because of its higher moisture content. In such cases, it’s important to keep the urine dilute, and “it has been shown that cats who eat wet food take in more water than those who eat dry food,” explains small animal kidney specialist Linda Ross, DVM. Cats who eat dry food don’t drink enough extra water to quite make up the difference.

This cat enjoys dry food but, for her health, canned would be fine, too.

On the flip side, dry food is a little better for dental hygiene than wet, but much more important to the health of a cat’s teeth are that you brush them regularly and take the cat for periodic teeth cleanings at the veterinarian’s office.

As for the rumor that dry food causes feline diabetes, it is just that — a rumor. Dry food, some of which is calorie dense,

can be particularly palatable (especially if it’s grain-free and low in carbohydrates), and some cat owners leave out more than a serving at a time in the mistaken belief that all cats can self-regulate the amount of food they eat without any portion control. But that’s not true, and the obesity that can ensue when cats are left to eat dry food ad libitum can contribute to the development of diabetes. It’s not something about the dry food itself.

It’s also a rumor that the preservatives in dry kibble are bad for cats. No proof of harm from preservatives used in cat food has ever been scientifically documented, whether the preservatives are natural (such as vitamin C) or artificial (like BHA or ethoxyquin, which manufacturers are moving away from not because of safety issues but because of market demand). To the contrary, there would be much harm without preservatives. Food spoilage resulting from faster rancidity could make a cat sick. (Food spoilage resulting from leaving out wet food too long could make a cat sick, too. The airtight storage that results from canning protects canned cat food, but once the food is opened and put in a bowl for the cat, it should be left out no more than a couple of hours.)

For all these reasons, at the end of the day, the choice of whether to buy your cat wet or dry food should generally not be driven by concerns about health.

Comments (2)

I completely agree with Jane. Cats are essentially the same obligate carnivores as pumas, lions, tigers, etc. The only cleaning their teeth get is when they gnaw on bones & tear flesh that has been contaminated with dirt. This action cleans their teeth - not crunching once on a bit of kibble.

Further, cats have a short digestive system and are unable to digest things like cellulose which is a major component of dry kibble. It's what makes the food stick together and gives it bulk. This results in higher volumes of smelly feces. My cats are fed a strictly meat diet and the volume & odor of their feces is greatly reduced. And most of them drink very little water since the meat diet is very high in moisture. None have ever had urinary tract or other health or dental issues.
Jim

Posted by: Jesse's Dad | January 2, 2017 11:24 AM    Report this comment

It's a myth that dry food has any beneficial effect upon tooth hygiene--many vets I've spoken with, matter of fact, have said that when a feline client presents with gum issues, often it's because s/he was given kibble, and a particle stuck under the gum line, and it inflamed the tissue.
Cats do not chew; they indeed have molars, but those have points, not flat surfaces, so a cat doesn't grind food. S/he either wolfs (!) each piece down whole, or chomps once. The hard piece doesn't stay on the tooth surface long enough to scrape anything away. Wet food slides down, being mostly water, but it isn't injurious to the mouth. In addition, I would politely argue that wet food is easier on the digestion (there's nothing in nature as hard as kibble--rodent, bird bones are 'soft, small and thin', says UC Davis researchers, who did a good study on the wet vs dry food debate), and cats rarely chew on the bird skull, in my experience. Wet is far better for hydration of any cat, and as cats don't have the thirst receptors (for lack of a better term) that dogs do, they don't drink enough, even when young and healthy. Jane Ehrlich

Posted by: Cattitude Feline Behavior | January 2, 2017 10:07 AM    Report this comment

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