When to switch your puppy to an adult diet


Why a puppy diet?

Feeding your puppy a nutritionally complete diet, tailored to their specific needs is vital for supporting optimal growth, and laying the foundation for a healthy future.

Depending on your puppy’s size and breed, they will have different nutritional needs during growth. The age at which your puppy will reach adulthood, also varies depending on your dog’s size – not the size they are now, but the size they are expected to be as an adult (see table below).


Expected Adult Weight

Age Adulthood is Reached

Recommended ROYAL CANIN® puppy diet

Small Breed: 1-10kg

10 months


Medium Breed: 11-25kg

12 months

ROYAL CANIN® Medium Puppy

Large Breed: 26kg-44kg

15 months


Giant Breed: >45kg

18-24 months

ROYAL CANIN® Giant Puppy


To ensure your puppy is appropriately supported throughout growth, they should remain on a tailored puppy diet until they reach adulthood. If you’re not sure what your puppy’s expected adult weight will be, consult your veterinarian for further advice.

Puppies have different dietary needs to adult dogs. There are a range of vital nutrients that your puppy needs during the first months of life to aid healthy growth and development. Puppy diets are typically higher in calorie, providing more energy to sustain their daily activities such as play, but also to support the growth of bones and muscles, and the development of body systems. Puppies also require a diet that is easy to digest, with prebiotics to support gut health, to allow their immature gastrointestinal tract to absorb maximum nutrition. A carefully balanced ratio of vitamins and minerals will also help support healthy skeletal development.

The diet you feed your pet during puppyhood will influence their health and eating habits for the rest of their life. ROYAL CANIN® Puppy diets are nutritionally balanced to offer a tailored diet to meet the needs of puppies of all sizes, and breeds.

Puppy Growth

There are several stages of growth for puppies.

From 2 to 4 months of age, puppies begin to wean from their mother. During this intense growth period, puppies need a diet rich in antioxidants to help support their immature immune system, and rich in prebiotics to help support healthy gut flora. As puppies continue to grow, they require the nutritional support of carefully balanced calcium, phosphorus and Vitamin D to support healthy skeletal growth and development. Your puppy will also be building its muscle mass through this time, relying on high quality, highly digestible protein in the diet to support this phase.

As they approach adulthood, your puppy’s digestive and immune systems continue to strengthen, but still require nutritional support to ensure your puppy avoids gastrointestinal upsets.

ROYAL CANIN® Puppy diets are specifically formulated to support growth in puppies of all sizes. Giant breed puppies are unique as they grow until they are 18-24 months of age – as such, they have two distinct phases of growth. ROYAL CANIN® offers two puppy diets to support Giant breed puppies - ROYAL CANIN® Giant Puppy from weaning until 8 months of age, and then ROYAL CANIN® Giant Junior, from 8 months to adulthood.


Neutering (or desexing) your dog is known to have many benefits to both your dog’s health and behaviour. But did you know, neutering can make your dog more susceptible to weight gain? The hormonal changes associated with neutering can impacting your dog’s metabolism, which in turn can impact how much food they need to eat. Once your dog is desexed, their daily calorie intake reduces by 30% - that’s one third of their daily portion! Furthermore, within 2 days of the procedure, your dog’s appetite may increase by up to 20%!

Even though your dogs daily energy needs change once they are neutered, it is important that we don’t simply reduce their daily food intake by 30%. If we do this, your dog may miss out on key nutrients that they need for health - plus it could leave them very dissatisfied! 

As neutered puppies and dogs have very specific nutritional needs, there are diets available that are specifically tailored for this life stage, such as the ROYAL CANIN® Neutered range. These diets have adjusted calories and include specific nutrients such as L-carnitine to support your dog in maintaining a healthy bodyweight post neutering.

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