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Home > Dogs > Can an Adult Dog Eat Puppy Food? Vet Approved Facts & FAQ

Can an Adult Dog Eat Puppy Food? Vet Approved Facts & FAQ

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Dr. Maxbetter Vizelberg

Veterinarian, DVM

The information is current and up-to-date in accordance with the latest veterinarian research.

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Dogs are the perfect pet for people of all ages, and they come in a variety of shapes and sizes. Regardless of the breed or age of your dog, it is important to provide them with a diet that meets their specific nutritional needs.

You might be wondering, can an adult dog eat puppy food? The answer is yes—but for most adult dogs, it is not the ideal diet and may lead to health issues in the long term.

Puppy food is typically higher in calories and fat than adult dog food, which is why it is not recommended for adult dogs unless they have a specific need for it, such as pregnancy or breastfeeding.

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Is Puppy Food Safe for Adult Dogs?

Puppy food is perfectly safe for dogs of all ages. The recipes do not contain any harmful ingredients, and feeding it to an adult dog on occasion will do no harm.

However, while puppy food is safe for dogs of all ages, it is not the ideal diet for most adult dogs.

Puppies have different nutritional needs than adult dogs since they are growing and developing at a rapid pace. Puppy food is typically higher in calories and protein than adult dog food to help support their growth.

Puppy food also contains higher levels of certain minerals and vitamins that are essential for a puppy’s development, such as calcium and phosphorus.

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Image By: BearFotos, Shutterstock

Adult Food vs Puppy Food

  • Calories: The average puppy food contains 300–400 calories per cup, whereas adult dog recipes have 200–400 calories per cup on average. Many adult dogs only need about 300 calories per day, so feeding them puppy food can cause them to gain weight, particularly for small or inactive breeds.
  • Protein: Puppy foods contain about 22–32% protein on average, while adult dog foods have 18–28% protein. Puppies need more protein than adult dogs since they are growing and developing muscles. Excess protein may be harmful to adult dogs with underlying kidney or liver issues as it can put additional strain on these organs.
  • Fats: Puppy foods contain about 8–16% fat on average, whereas adult dog foods have 5–15% fat. Fat is a concentrated source of energy and helps puppies grow and develop. Adult dogs do not need as much fat in their diet, and too much fat can lead to weight gain.

Long-Term Risks

While an adult dog can technically eat puppy food, it is not the ideal diet for them. Puppy food is too high in calories and fat for most adult dogs, which can lead to weight gain if fed on a regular basis.

It is best to feed your adult dog an adult-formulated food, as it will better meet their nutritional needs and help them maintain a healthy weight. If you are unsure of what type of food to feed your dog, consult with your veterinarian for recommendations.

Can Puppies Eat Adult Dog Food?

While it is not recommended to feed puppies adult dog food on a regular basis, they can eat it on occasion without any harm.

The main difference between puppy food and adult dog food is the calories and protein content. Puppy food is higher in both of these nutrients to support their growth and development.

Adult dog food does not contain the same levels of these nutrients and may not provide puppies with everything they need to grow and develop properly.

Specially formulated puppy diets are designed to meet the unique nutritional needs of puppies and are the best option for them.

jack russell terier puppy eating food from bowl
Image By: Gladskikh Tatiana, Shutterstock


How Dogs Nutritional Requirements Change Through Their Lives

Your dog goes through a lot of different stages within their life, and their nutritional needs change change as they do. A dog’s diet is the basis of their metabolism and sustaining their life processes, which is why it is so important to understand their needs at each stage.

The length of a dog’s life stage depends on its breed, specifically the size of its breed. For example, giant breeds are considered puppies for up to 2 years and should be fed puppy food as such, while small breeds can transition to adult food at 10 months old.

Dog Size Puppy Adult Senior Geriatric
Small (up to 20 pounds) Up to 10 months 10 months–10 years 10–16 years 16+ years
Medium (21–50 pounds) Up to 1 year 1–9 years 9–13 years 13+ year
Large (51–100 pounds) Up to 15 months 15 months–7 years 7–12 years 12+ years
Giant (100+ pounds) Up to 24 months 2–6 years 6–9 years 9+ years


Puppyhood is a crucial time for your dog, during which they will grow and develop rapidly. Puppies need a diet that is high in calories and nutrients to support this growth.

Puppy food is typically higher in calories than adult dog food, as well as being more easily digestible. It also tends to be fortified with more essential vitamins and minerals to support your puppy’s growth and development.


As your dog reaches adulthood, their metabolism will start to slow down and they will begin to burn fewer calories. This is why it is important to switch to adult dog food once they reach maturity. Adult dog food is typically lower in calories and fat than puppy food, as well as being more nutritionally balanced.


As your dog enters their senior years, their caloric needs will decrease even further. Senior dog food is typically designed to meet the specific nutritional needs of older dogs, such as joint support or weight control.

In the later years of a dog’s life, it is especially important to maintain a nutritionally balanced diet to help keep them healthy and active.

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Image By: Jaromir Chalabala, Shutterstock


If your female dog is pregnant or nursing, she will have increased caloric and nutritional needs. Pregnant and nursing dogs should be fed a diet that is rich in protein and fat to support the growth of the puppies.

Many veterinarians recommend feeding a pregnant dog a diet of puppy-formulated food during her pregnancy and while she is nursing, as it will provide her with the extra calories and nutrients she needs.

Even past pregnancy, as she lactates and nurses, she will need more calories than she did prior to becoming pregnant, so puppy food can be continued for a few months postpartum. This diet not only sustains her but also her puppies via her milk supply.

Intact or De-sexed

Intact (not spayed or neutered) dogs have different nutritional needs than those that have been spayed or neutered. Intact dogs require more calories and protein to support their reproductive organs, as well as their overall growth and development.

On the other hand, spayed and neutered dogs have a reduced need for calories and protein, as they no longer have reproductive organs. This is why it is important to feed them a diet specifically formulated for their needs.

Make sure you’re feeding your dog the right amount and type of food for their lifestyle, check out our dog food calculator here:

The exact amount of calories an individual animal needs to maintain a healthy weight is variable and influenced by many factors including genetics, age, breed, and activity level. This tool is meant to be used only as a guideline for healthy individuals and does not substitute veterinary advice 


Final Thoughts

Just like us humans, dogs go through many stages in their lives. At each point, their bodies have different nutritional requirements. It is important to be aware of these changes and to adjust their diet accordingly.

Puppy food is best left to the pup, as they need the extra calories and nutrients to support their growth. Once they reach adulthood, though, it is time to switch them to an adult diet.

While there are general guidelines for what type of food to feed your dog at each life stage, it is always best to consult with your veterinarian to ensure that you are providing your dog with the best possible nutrition.

Featured Image Credit: Emolaev Alexander, Shutterstock

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