Can a Kitten Eat Adult Cat Food?

If you’re a cat parent, you’ve probably, at one time or another, been tempted to get more than one cat. Once the inevitable happens, and you have a small zoo of cats, feeding time might get dicy. What if your curious new kitten really wants in on your grumpy adult cat’s food (if they’ll share). Can kittens eat adult cat food?

In short, the answer is no. Kittens cannot eat adult cat food. Growing kittens and adult cats have different nutrition needs. Don’t worry, it’s not too complicated. We talked to two veterinarians to get advice on the best food to feed kitten and how to deal with feeding multiple cats who need different foods.

Understanding nutritional requirements for kittens

Kittens develop at an impressive rate. To fuel that extraordinary growth, they need more calories than fully grown adult cats. Kittens also need certain nutrients in different ratios than older cats.

“Just like in people, nutritional requirements change throughout the course of a cat’s life,” says Dr. Chris Konvalinka, a veterinarian at Bahama Road Veterinary Hospital in Bahama, North Carolina. “Kitten food is designed to provide more protein, calories, fat, vitamins, and minerals to meet the needs of rapidly growing bodies. In adulthood, those requirements change, and therefore the foods should change as well.”

Protein, fat and caloric intake

Kitten food, sometimes called “growth formula” on the package label, provides higher levels of protein, fat, and calories compared to adult cat food (sometimes called “maintenance formula” in the label).

The American Association of Feed Control Officials (AAFCO), which maintains standards for pet food, recommends that kitten food contain at least 30 percent crude protein and 12 to 24 percent fat. This percentage refers to the food’s “dry matter” content, which accounts for the amount of water in the food. In comparison, adult cat food has at least 26 percent protein and at least 9 percent fat.

Thanks to its higher fat content, kitten food is more energy dense — contains more calories per ounce.

Omega-3 requirements

Omega-3 fatty acids — in particular, EPA and DHA — are critical nutrients for kitten development. AAFCO recommends that kitten foods have 0.012 percent combined EPA and DHA. In comparison, adult cat food has no AAFCO minimum recommendation for EPA/DHA. Not all adult cat foods contain omega-3 fatty acids, though adult cats might still benefit from these nutrients. DHA is especially important for kittens as it helps support healthy brain and eye development. Omega-3 fatty acids are also helpful for skin, coat, and the immune system.

What's the difference between kitten food vs adult cat food?

The three major differences between kitten food and adult cat food include:

• Nutrient composition and caloric density: Kitten food has more protein and fat, and is more calorie dense than adult cat food. It also contains different levels of vitamins and minerals compared to adult cat food.
• Texture and size of kibble: Dry kitten food tends to have smaller sized kibbles for small mouths.
• Supplements and additives: Kitten food always contains omega-3 fatty acids, which are not always found in adult cat food.

Can you feed your kitten adult cat food?

No, you shouldn’t feed your kitten adult cat food. According to Preston Turano, a veterinary spokesperson at Felix Cat Insurance, adult cat food does not have the nutrition profile needed for growth and development.

“If adult food only is fed to a kitten, it can slow or even harm their development,” he says. “If you have multiple cats and your kitten accidentally gets into the adult food it will not hurt them, but their main diet needs to be formulated for a kitten.”

How to feed cats of different ages

If you have an adult cat and a kitten, it is possible to feed them the same food. You would just have to choose a food labeled for “all life stages,” which means it meets the nutritional needs of both kittens and adult cats.

However, Dr. Turano recommends talking with your veterinarian about whether that’s the best option, rather than just an adequate option, for your cats. “It is generally better to do separate feedings with the most appropriate diet so your growing kitten can get the best nutrition for development,” he says.

Diets formulated for all life stages tend to be higher in fat and calories than adult cat food, so they might not be a good option if your adult cat is overweight. Additionally, Dr. Konvalinka points out that some senior cats, especially those with medical conditions, might have special nutritional needs that wouldn’t be met by an “all life stages” diet.

When to switch a kitten to adult cat food

Dr. Turano confirms that the best age to switch a kitten to adult food is somewhere between eight months to one year of age, once they’ve completed the majority of their growth. If you’re not sure about the timing of the switch, have a chat with your veterinarian, who can make personalized recommendations for your cat.

Anytime you change your cat’s food, do so gradually, over a period of days or even weeks. This will help to avoid stomach upset. Slowly mix increasing amounts of the new food into the old until the cat has transitioned completely to the new food.