puppy sleeping by food bowl

Transitioning Your Puppy To An Adult Dog Diet

The months are flying by and your puppy is growing quickly! Soon, it will be time to think about choosing a diet for their next stage in life.

Your puppy is growing quickly, and it will soon be time to leave the puppy food behind and move on to feeding a diet designed for young adult dogs. Take a look at our guide below to feeding your young adult dog.

Find your local vet

Most brands of dog food produce lifestage diets. This means that the diets have been formulated to provide the right levels of nutrients to support your puppy as they grow to adulthood and later, as they become a mature and senior dog.

Small breed dogs tend to reach their adult size relatively early, while large and giant breed dogs may take much longer to get there. This needs to be reflected in the way we feed our dogs, in order to help them to grow at the correct rate and to develop lean muscle and healthy joints. Most small- to medium-breed dogs will be ready to transition to a food for young adults by about 10-12 months of age. For large and giant breed puppies, this dietary change isn’t normally appropriate until 12 to 18 months. Your vet team will be able to help you to choose the right time to phase in adult food.

You’ll already have worked out what types of food your puppy likes – perhaps you feed dry kibble or maybe they prefer a mixture of kibble and pouches. Just like with puppy food, there is a huge variety of adult dog food out there, so you should be able to find a diet your puppy enjoys as they grow into adulthood. You may decide to stick with the same brand as the puppy food you’re currently using, but it’s still a good time to take stock and make sure you’re providing your puppy with the best nutrition you can. So, how do you know which food to choose?

Dogs are omnivores who evolved to live around early humans, feeding on scraps and picking through village rubbish tips. This doesn’t mean that we should be content to feed our modern-day dogs rubbish – quite the opposite – but it explains why, to various degrees, dogs can digest a variety of food types, including meat, fish and offal, some fruits and vegetables, oils and fats and an amount of carbohydrate, including grains.

We need to provide our dogs with good quality nutrients, including proteins – which allow them to make new body tissue; and fats and oils – not only do dogs obtain a large proportion of their energy from metabolising fats, but also, fats and oils help them to absorb certain important vitamins. It’s almost never necessary to supplement a commercially made diet with extra vitamins or minerals. In fact, it can lead to bone and joint or metabolic problems if you do. Dry food is available in appropriately sized kibbles to suit different sizes of dog. With some brands, there are even breed-specific varieties. Both wet and dry foods come in different flavours, so it’s often worth buying a small pack of whichever new diet you choose, just to be sure your young dog likes it. Pack size is also important when you consider how long it may take to use it up.

Dry food should always be sealed down or kept in an airtight container to keep it fresh, while opened tins or sachets must be refrigerated and used within the time specified on the packaging. If you have one very small dog, it’s best to buy smaller pack sizes to make sure the food stays fresh.

Some dogs have sensitive tummies, while others seem to be able to get away with eating all sorts without any problem! Nevertheless, with very few exceptions, it’s a good idea to introduce a new diet and phase out the old one over about seven to 10 days. This allows your dog’s digestion to get used to new ingredients and it also gives your dog a chance to develop a taste for the new food. Many dogs will eat anything they’re offered.

However, for those who are a bit pickier, taking the time to let them try new tastes and textures over a few days can help to prevent them rejecting a diet outright when it might otherwise have suited them. You could mix old and new diets together, but it can often work well to offer a sample of the new diet before you serve the rest of your dog’s meal. This way, they’re more likely to be hungry and willing to try a new food, but if they aren’t interested and don’t finish the new food, they will still be able to have most of a normal dinner afterwards.


No matter what the dog’s age, we should always be aiming to provide good quality nutrition to help them to build lean muscle and to provide them with enough energy to suit their lifestyle. A lively young spaniel will require more energy from their diet than a less active type of dog. Diets designed for working dogs are just that – they are tailored to supply higher levels of energy than many pet dogs require. Dogs of working breeds only require a diet like this if they are actually working, or are very active.

One of the big challenges is to keep dogs to a healthy bodyweight. Being overweight is associated with a number of life-shortening diseases, including: arthritis and other joint problems, cancer, breathing problems and heatstroke. Recently, it was reported that almost half of the UK’s dogs were overweight – that’s a huge number of dogs at risk of serious illness. One of the easiest ways you can take the best care of your dog is to keep them to a fit and healthy bodyweight.

Your vet team will check your dog’s body condition score every time you visit. You can also learn to check this yourself. It’s a bit different to simply monitoring bodyweight, because it helps you to decide whether your dog is carrying too much or even too little body fat for their shape and size. If you’re concerned that your dog’s body condition score may be too high or too low, you can ask your vet team to check for you and if necessary, the food allowance can be adjusted.

Some diets are formulated to support specific body systems. For instance, some are designed to assist with dental health, while others may be aimed at promoting healthy joints. Added benefits like these can be great and they’re often included in standard diets.

When you’re looking for a new dog food, there’s such an array on offer! You may already have an idea of which types or brands of food you might choose, so it’s worth knowing a bit more about what you’re buying. Strict rules govern the information pet food manufacturers must provide on their packaging.

Labels must state whether the food is a complete diet which, when fed at the recommended quantities, provides the right balance and levels of all the essential nutrients; or whether it’s a complementary pet food, such as a mixer or treats – designed to be fed alongside other foods in order to contribute to a balanced diet. There are two further areas of interest when you’re looking pet food labels: the composition and the analysis.

Let’s find out a bit more about each of these in turn… The composition tells you which ingredients have been used. They’re listed in order of the greatest first, by weight. Sometimes, a label may list ‘meat and animal derivatives.’ Depending on exactly what those animal derivatives are, it doesn’t necessarily mean the diet is of low quality, as offal and other ‘non-meat’ animal products can contribute important nutrients. Sometimes, the specific animal-sourced ingredients may vary by batch, depending on availability, but if a label states that there is, for instance, a minimum of 4% chicken, then that will remain the same between batches.

The animal products used must still have been sourced from animals fit for human consumption and they are often simply surplus to the human food industry. The quality of the ingredients used is normally reflected in the price, even when the nutrient analysis is similar to that of a higher or lower-priced food. Ingredients that haven’t been sourced from animals can vary widely. At one time, it was thought that grain wasn’t good for dogs. Only rarely are dogs truly cereal grain intolerant, and grains can provide some important benefits when fed to dogs, so there’s no need to avoid it as an ingredient.

The analysis section of a pet food label tells you what the diet provides when it’s broken down. The information tells you, among other things, how much protein the diet contains, how much energy it provides, and how much fibre. The puppy food you’ll have been using up until now will be relatively high in protein (typically around 30%) and calories, to support growth. As your puppy’s growth slows down, their nutritional requirements will change, and an adult diet will reflect this. If you were to carry on feeding a puppy diet to your dog once they’d finished growing, they would no longer be getting an optimal balance of nutrients and they’d also begin to store some of the surplus energy from the diet as body fat.

By the time your puppy is old enough to be ready for an adult diet, they could probably manage most of the treats and chews available. However, treats can be a big cause of weight gain in dogs, so check the label for the recommended daily allowance and err on the low side of this. Choose healthy or natural treats where possible – for instance, lots of dogs love a whole carrot, or a slice of apple to chomp on. Keep in mind also, that a new type of treat to your dog is also a new type of treat to their digestive system, so introduce them gradually.

Chews can be a great way to satisfy your dog’s behavioural needs, while also benefiting their teeth. Chewing helps to keep teeth clean, while also strengthening the ligaments that hold the teeth in their sockets. Chews do contain calories, so keep an eye on how many your dog may be consuming in an average week. It can be tricky to find the right sort of chews for individual dogs – some lose interest if they aren’t making good progress on very tough chews, some will chomp through them like a machine, while others may bite down so strongly on very hard chews that they damage their teeth! You’ll know your own dog, so you’ll be able to find the right type of chews that fulfil their behavioural needs, without filling their tummy too much.

It can be useful to keep a note of how many treats, chews and ‘extras’ your dog receives over the course of a week, especially if more than one person might feed them. A good way to do this is to tape a sheet of paper onto the fridge door, or to use a whiteboard or kitchen calendar. Each time anyone gives the dog anything to eat or chew, they record it. It’s often a surprise when everything is added up at the end of a week!

Once puppies have been weaned, all they need to drink is a constant supply of clean, fresh water. There’s no need to offer milk – in fact, this can upset their tummies. When out and about, try to discourage your dog from lapping from muddy puddles or from ponds, and always stop them from drinking seawater, when visiting the beach.

By choosing the best quality diet you can afford, introducing it gradually at the appropriate age, and keeping a close eye on your growing dog’s energy levels and body condition, you’ll be setting them off to a good start for the next chapter of their life – adolescence and adulthood!

Health Plans to keep your puppy healthy

At Vets4Pets we offer a range of Health Plans that make essential routine treatments more affordable. You'll save money on things like annual vaccinations, flea and worm treatment and routine health check-ups.


Join our free VIP Puppy club

Join the club for expert advice and tailored offers, including £30 off our Complete Care Health Plans


Puppy & Kitten Advice

Giving your pet the best start in life begins with getting the best expert advice.

This site uses cookies to store information on your computer in order to improve your experience. To find out more about the cookies this site uses, please see our cookie policy and privacy policy.