Yes, an adult cat can eat kitten food, but most healthy adults should not eat it daily. Kitten food contains more calories and nutrients than a cat requires, and over time, the extra calories become extra weight. It can be beneficial for some adult cats. Before you give kitten food to your cat, consult with a veterinarian about your cat’s diet.
Does Kitten Food Affect Adult Cats?
Technically yes. Kitten food isn’t poisonous like a toxic food would be; it’s just for a different age. But for a healthy adult, it’s not a good day-to-day option, as the food is too rich and the calories quickly accumulate.
It can be beneficial to a few groups of adult cats, and you will meet them below. All other cats will match the complete adult food.
Difference Between Kitten and Adult Food
Kittens grow very quickly. They require almost double the amount of energy as an adult cat between 2 and 4 months of age, and gain weight at a rate of 100 grams per week between 4 and 5 months.
Kitten food is designed for that “big leap. Let’s look at the differences between adult food and kitten food.
- Protein: The standard nutrition guidelines say that kitten foods should have at least 30%, while adult foods have at least 26%, and many kitten foods have between 35% and 50%, whereas many adult foods have between 25% and 40%.
- Calcium: The minimum is 1.0% for kitten food and 0.6% for adult food.
- Phosphorus: The minimum for kitten food is 0.8% and for adult food is 0.5%.
- Fat and calories: Kitten food typically has a higher fat content, and thus more energy for your cat, per bite.
The fat minimums are the same in both phases, so the actual difference is printed on the label of the food purchased. Carefully read that label before you make your decision.
High-quality protein is also needed for growing kittens, as a deficiency in protein will retard growth. Extra calcium is also required for growing bones, and a mature cat does not require any additional calcium.
What Happens If an Adult Cat Eats Kitten Food?
The main risk is weight gain. If your cat consumes more energy than she expends, her body stores any energy that is not needed as fat.
This is not something to take lightly, as a 2022 study of cats revealed that 61% were overweight or obese. 28% of owners in the same survey described their cat as being normal weight when veterinarians said otherwise, meaning that many owners don’t detect the problem until it is well advanced.
Extra weight also raises your cat’s risk of diseases such as diabetes and arthritis.
One 26-week study of 24 cats demonstrates the rapid increase in weight. Neutered cats gained 53.8% of their body weight, intact cats gained 27.1%, and a high-fat diet exacerbated the body weight gain in the neutered cats.
In that study, they did not study kitten food, but dietary fat and energy. However, kitten food has a higher content of both.
There is no direct test for adult cats as to the safe amount of kitten food, so no one can say. This is where the expertise of your veterinarian is needed.
When Can Adult Cats Benefit?
Some adult cats require the additional fuel. Please consult your veterinarian before taking any action.
- A Pregnant cat: A high-quality kitten or growth food is suitable for a pregnant cat. Her consumption typically increases by 25% in the final third of pregnancy, and may increase by up to 40% during this time. Select a food that has been successful in a feeding trial for pregnancy and nursing, and change her before breeding, not during pregnancy.
- Nursing mothers: Milk requires a lot of energy, so a nursing cat can consume 2-3 times her normal amount, depending on litter size. Kitten food is energy dense – this is good as her tummy is small.
- Senior cats: If a senior cat (over 11 years old) has a poor appetite, they may do better on a richer food, as a smaller amount of it now provides more nutrition.
- Cats that are picky eaters: The greasiness of the food may entice a cat that would not eat other food. Use this as a temporary solution.
Do not guess at the cause of weight loss or poor appetite, your vet can help find the cause.
Can You Feed Kitten Food Every Day?
No, for most healthy adults, kitten food is intended for growth, and growth stops. Kittens are considered weaned by 8 weeks of age, and most cats are adults at 12 months, some large breeds at 14 months.
At that stage, normal adult cat food is more appropriate, as continuous feeding kitten food will result in weight gain.
Only a vet should recommend daily feeding, such as for pregnant cats, nursing cats, and certain senior cats.
If your cat has a health problem like kidney disease or diabetes, you should get your vet’s advice before making any changes to its diet. Never change their food without their permission.
If you have an adult cat in the house and a kitten, consult your veterinarian for a feeding schedule for the kitten to eat its own food.
How to Switch Foods
Sudden changes can upset your cat’s stomach, so mix the old and new foods slowly over 7 to 10 days. Here is a simple 10-day schedule:
- Days 1 and 2: 75% old food and 25% new food.
- Days 3 and 4: 50% old food and 50% new food.
- Days 5 to 7: 25% old food and 75% new food.
- Days 8 to 10: 100% new food.
Observe your cat as it changes over, and be aware that fussy cats can take up to 40 days! If you have vomiting, loose stools, or a decreased appetite, take a few more days on each step. If the symptoms persist for over 24 hours, contact your vet.
Do not allow a cat to “hold out” for the new food. If a cat refuses to eat or drink for 2-3 days or more, a veterinarian should be seen immediately, as fatty liver disease is a serious condition that can develop rapidly in overweight cats.
Be aware of hiding, vomiting, yellow gums or eyes, and decreased energy.
How Much Kitten Food Can an Adult Cat Eat?
There is no one safe amount of kitten food for all cats because the answer depends on your cat’s weight, age, and activity.
Begin with the number of calories you need each day. A healthy adult cat requires approximately 50-70 calories of food per kg of body weight, and a neutered 4kg cat should be consuming approximately 240-280 calories per day. Cats between 7 and 10 years old might require 20% to 30% less calories than this.
Kitten food is included in that amount. Does not sit on top of it.
Treats and extras should be no more than 10% or less of daily calories, which is about 24 to 28 calories for that 4 kg cat. If feeding kitten food into a meal, remove the same amount of calories from the meal.
The calorie counts vary from one product to another, so look on the label or contact the manufacturer, as many cans will not specify calorie content.
Obesity in the middle-aged cat is more likely, and it’s important to monitor your cat’s body shape regularly, not just when the scales start to budge. A healthy weight will allow you to feel ribs without seeing them and will allow you to see a waist from above. If you can’t feel the ribs, it means that your cat has extra weight. Vets rate body shape from 1 to 9, with a score of 4 or 5 being perfect.
Final Verdict
Adult cats can eat kitten food, but it works best as a short-term tool, not a daily meal. Pregnant cats, nursing mothers, and some seniors with poor appetite can benefit from the richer formula, while most healthy adults do better on food made for their age.
Weight gain is the biggest risk, and many owners miss it until it is well along. Count calories, switch slowly, and watch your cat’s body shape.
Before you change your cat’s diet, ask a vet and consider an online consultation with VirtualVetDesk.
FAQs
Can a kitten eat adult cat food?
A kitten can eat it, but should not stay on it, because adult food does not match the calories and minerals that growth needs.
At what age should my cat switch from kitten food?
Switch at around 12 months for most cats, and longer for some large breeds. Ask your vet when your cat is ready.
Will kitten food make my cat gain weight?
It can. Kitten food is richer, so an adult cat that eats it regularly may store the extra calories as fat.
Can I give kitten food to my picky senior cat?
Maybe, but ask your vet first, because poor appetite in an older cat can signal a health problem that needs treatment.
Why does my adult cat keep stealing the kitten’s food?
Rich food tastes good to cats. Feed them in separate spaces and ask your vet for a plan.
