Switching from Kitten to Adult Cat Food

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Switching from Kitten to Adult Cat Food

As your kitten grows up, their nutritional needs change with them. This means they’ll eventually need to be moved from a diet of kitten food onto adult food. While this may seem like a minor change, it plays a huge role in your cat's overall health and wellbeing.

Knowing when to switch your kitten’s diet, and how to make the transition, is really important for making sure they’re getting the nutrients they need and avoiding an upset stomach during the changeover. At this stage, you’ll also need to decide which cat food you think will best suit your pet and any specific dietary needs they may have.

Why are there different cat foods for different ages?

Cats have different nutritional needs at different stages of their lives, and their pet food formulation should reflect this. It may also mean that the ingredients in cat food for adult cats differs slightly to that of kittens. Kittens need a diet that is rich in proteins, fats, and calories to support their growth and development, while adult cats need to be fed nutritional levels for adult maintenance requirements. Care must also be taken to prevent obesity and other related health issues. Their nutritional needs change again as they reach their later life, with senior cats needing diets that support their ageing bodies.

When to switch their food

It's usually recommended that you start transitioning your kitten to adult cat food when they are around a year old, however, this can vary depending on their breed, size, and overall health. If in doubt, have a chat with your vet to determine when the best time is to make the switch. It's worth noting that some kittens may require a special diet after their first year, such as those with certain health issues or breeds that tend to be susceptible to certain diseases.

How to make the food switch

When making the switch from kitten to adult cat food, you should do it gradually, as sudden changes in your cat's diet can cause stomach upset, vomiting, and diarrhoea. Start by mixing a small amount of adult cat food into their kitten food, gradually increasing the ratio of adult food to kitten food over the course of a week or two until your cat is fully transitioned. Make sure they always have access to plenty of fresh water to help keep them hydrated too.

Choosing the right adult cat food

Choosing the right adult cat food can seem like a tricky task, considering the wide range of options available in the market. To pick the best food for your pet, you should consider your cat's current health, activity level, and any specific dietary needs they may have. Look for high-quality brands that offer healthy ingredients and balanced nutrition tailored for their life stage. Here at the OPTIMUM™ brand, we believe that what a cat eats at each stage of life has a powerful effect on their growth, strength and total well-being, so we offer tailored ranges for kittens, adult cats and mature cats.

Easing your cat into the switch

As you transition your cat to an adult diet, keep a close eye on their behaviour and health for any signs that they’re off their food, or experiencing diarrhoea, or vomiting. If they do lose their appetite or suffer from a stomach upset, swap them back onto their kitten food for a few days before beginning the transition again at a slower pace. Some cats may need more time to adjust to the new food, while others may transition with ease.

To help with the process, you can try feeding your cat smaller portions of adult food throughout the day instead of one large meal. This will help them get used to the new diet without overwhelming their digestive system. However, if issues persist, speak to your vet for their advice.


Switching from kitten to adult cat food may seem like a small step, but it can make a huge difference in your cat's overall health and wellbeing. Make sure you get the timing right and take your time when transitioning your cat into their new diet to prevent any stomach upset along the way. For more tips and advice on your cat’s nutrition and health, check out our pet care blog.

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