The difference between puppy food and adult pet food

We look at the differences between puppy and adult dog food, why you should use it and how long for. Plus our top tips for the best puppy food.
What to look out for with puppy food

Ever wondered or even a bit baffled by the number of options for dog food in your supermarket? You’ll find food for puppies, adult dogs, then to senior dogs from a number of different brands. Then couple this with new online pet food subscriptions, raw food diets, vegan pet food, insect based food and more it can be difficult to understand what’s best for your furry friend. 

We’ve taken advice from our resident veterinarian Rebecca Wilkinson RVN to help shed light on why puppy food is needed, how it promotes development of your pooch and which foods are available. 

What is the difference between puppy food and adult dog food?

Puppy food is available in a kibble or wet/moist food. The kibble is often smaller, to allow their smaller mouth and baby teeth to manage it. More recently puppy food has been subdivided into breed size categories, to further give specialised nutritional support to size related health conditions, for example increased omega fatty acids and added glucosamine for the large breed dogs to help towards preventing joint disease.

The key differences between the nutrients and minerals in puppy food and adult dog food are shown below:

Nutrient Puppy Food Minimum Adult Food Minimum
Protein (%) 22.0 18.0
Lysine (%) 0.77 0.63
Fat (%) 8.0 5.0
Calcium (%) 1.0 0.6%
Sodium (%) 0.3% 0.06%
Chloride (%) 0.45% 0.09%

*Source: PetMD

What should owners look for in quality puppy food?

As puppies’ bodies grow, they require an intricate balance of vitamins, minerals and macronutrients like protein, carbohydrates and fats. 

Puppies need a higher level of protein to fuel their muscle development and increased calcium to support skeletal growth. Many foods even have added DHA to improve brain development. Without this nutrient rich food they can develop health problems such as skeletal issues.

The puppy food should have supported the growth and development of the puppy and now a ‘maintenance’ adult diet will take over. Kibble is often bigger, the flavour range and options becomes wider. Breed specific diets are still available if required but the nutrients will now be balanced to maintain body weight and energy levels.

Is dry or wet food best?

Wet food has large amounts of moisture (water) added to it which can often mean having to feed larger quantities of it to get the same amount of nutrients. It is generally more expensive than dry food but many dogs find it more palatable than dry food. Some owners mix dry in with wet food to add palatability to the meal.

Dry food tends to be easier to manage due to it being stored easily, more cost effective, easier to measure out (important to those dogs trying to lose weight) and generally more convenient. Dry food can also be one of the ways to manage your dog’s dental health….but this only works if they chew their food!

All life stage pet food is it a good thing?

You may find there are a number of pet foods out there that claim to be for all life stages, effectively meaning that you can feed your pet the same food if they are a puppy, adult or senor dog. There’s a lot of debate about whether these are a good option for your dogs health. 

Studies have shown that the minimum requirements for puppy in the development phase are higher for all elements nutrients are higher than the adult phase, which makes sense, but in some cases – protein intake for example – it it likely to be perfectly fine to feed all life stage pet food to puppies, adults and senior pets. However, this may not be the case for other essential nutrients where it would be more important to modulate their intake at different life stages. 

How long should puppies be on puppy food?

We all understand that a dog’s lifespan is shorter than ours, therefore the life stages are also shorter. A dog may only be classed as a “puppy” for the first year or so of its life. This can also change depending on the breed and size of the dog. Generally the transition to adult food should begin as they start to reach their adult height.

The puppy will be transitioning over to adult food between 10 and 18 months, again, depending on breed. For example, a Yorkshire Terrier may be classed as fully developed by 10 months but a Saint Bernard may not be mature until 2 years of age.

As a rough guide on when to transition to adult food see the table below:

Dog Size (when adult) Age at which to consider transitioning to adult food
Small (under 10kg) 9-12 months
Medium (10kg – 20kg) 12-15 months
Large (20kg+) 12-24 months


Why switch from puppy food to adult food?

Puppy food is designed to promote healthy growth in your puppy and give them the nutrients they need to build healthy and strong bones and muscles. Clearly as your puppy grows into adulthood then the growth phase is coming to an end and therefore the nutrients that your dog needs is no longer to promote growth but rather maintain a balanced and healthy lifestyle – more focused on maintaining a healthy weight. Then as your pet then approaches later life their dietary needs will change once more. 

How to transition from puppy to adult dog food

Making the transfer to adult food can usually be done fairly quickly but you’ll want to be careful that you don’t cause any stomach upsets or diarrhoea it is best to stagger the amount that you give over the course of a week. 

For example for the first couple of days you could introduce the adult food by mixing a small amount with a majority of puppy food. 

Then on days 3 and 4 you could split the food half and half between adult and puppy food. 

Gradually over the course of the next 3 days slowly increase the amount of adult pet food until you have full transitioned to 100% adult pet food. 

This should enable a smooth conversion to adult food. 

Can you feed puppy food to adult dogs?

You can feed puppy food to adult dogs, it won’t do them any harm – at least not in the long term. For the odd meal, perhaps if you’ve unexpectedly run out then it’ll be fine but if this becomes a trend longer term then you’ll be feeding them with a different nutritional balance than they no longer need. 

The intake will be more focused towards promoting healthy growth into adulthood, but when they’ve already made it to that adult stage then long term feeding of puppy feed to adult dogs could likely result in weight gain, which is something that can then cause more complex issues.  

Recommended puppy foods

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