Hepper is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Dog Fasting 101 – Vet Reviewed Risks & Benefits

Ashley Bates

By Ashley Bates

Black Boston Terrier

Vet approved

Dr. Paola Cuevas Photo

Reviewed & Fact-Checked By

Dr. Paola Cuevas

MVZ (Veterinarian)

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

Learn more »

Is intermittent fasting for dogs a new age craze, jumping on board with fad diets across the pet food industry? Not necessarily. You might be interested to know that fasting has very ancient roots for dogs, although at some point, we wouldn’t refer to it as that.

In the wild, dogs’ primal ancestors didn’t eat on timed schedules every day. Sometimes, days would pass trying to find a new food source. So, you could say your dog’s body is designed for intermittent fasting. Let’s get all the details on benefits and potential risks.

Divider 7Intermittent Fasting Can Be Fantastic for Canine Health

Healthy adult canines with no known health issues can fast beautifully with endless benefits. Think of intermittent fasting as a total body reset—both for you and your pups.

Even though the benefits are vast, there are things to consider before choosing to fast. We will remind you once and remind you again to always check with your veterinarian before making any significant lifestyle changes for your dog.

dog in front of the empty bowl
Image Credit: Jaromir Chalabala, Shutterstock

Why Fasting Has Primal Roots

In the wild, meals can be very scarce for canines. On average, wolves eat roughly three times per week if they do well on hunts. So, originally, your canine’s system was designed for stretches of food scarcity.

While it seems like these wolves are starving, it helps their bodies rest, restore, and reset. Fasting activates the hormone glucagon, which keeps blood glucose levels balanced by reducing insulin secretion. Intermittent fasting also enables the dog’s body to get rid of certain imperfect cells through a process called autophagy.

divider 9The 6 Health Benefits of Fasting for Dogs

If you have a healthy adult, the benefits of fasting are numerous, to say the least. This process enhances all of your dog’s bodily functions and helps them maintain optimal health.

1. Fasting Enhances Immune System

When your dog fasts, it empowers a macrophage, clearing your dog’s body of bacteria and viruses.

Macrophages are special immune cells that destroy and consume pathogens and deadly or abnormal body cells. They clear up any cellular debris left behind after inflammation. They also boost the immune system to reduce inflammation, improving autoimmune health.

Dog Healthy Teeth
Image Credit: Lucia Romero, Shutterstock

2. Fasting Improves Mental Performance

Dog professionals speculate that your pup will have improved mental focus thanks to fasting. That is because fasting can lead to neural regeneration, so it keeps their minds sharper than average.


3. Fasting Can Help Lower Insulin Levels

If your dog has diabetes, you should always get veterinary guidance on managing their illness. However, studies show intermittent fasting can alleviate high insulin levels, reducing systemic inflammation.

So, with your vet’s okay, you can try intermittent fasting. If you notice any adverse reactions, you might need to stop altogether.

vet checking boston terrier dog
Image Credit: Nestor Rizhniak, Shutterstock

4. Fasting Purges Harmful Bacteria

When your dog’s body is in the process of fasting, the body starts to become an unfavorable host for certain types of bacteria. The body will attack these harmful bacteria, eliminating them from your dog’s system. It’s a fantastic way to reset gut flora.


5. Fasting Promotes Tissue Regeneration

Intermittent fasting is directly connected with tissue regeneration. It targets abnormal body cells, damaged cells, dead cells, and even tumors. This process makes the body direct its energy to kill the damaged cells and convert them to energy.

vet carrying boston terrier dog
Image Credit: Zakharova_Elena, Shutterstock

6. Fasting Can Help Weight Loss

When done correctly, intermittent fasting can promote a healthier diet. As your dog gets acclimated to this, their weight can regulate as a result. They can keep their figures fit, muscular, and toned.

divider 9Things to Consider

As with any other dietary change, you must do things correctly. Fasting is generally safe for healthy adults, but these matters can change depending on the circumstance. There are a few examples of when fasting is not the best approach.

Puppies, Seniors, and Pregnant Females Require Special Nutrition

Some dogs need an extra boost of nutrition to maintain, grow, or provide. Puppies, seniors, pregnant and nursing females need a little more nutrition than the average dog. It is not positive for them to go long periods of time without eating, so fasting is not recommended in these cases.

It would help if you only allowed healthy adult dogs (over one year of age) to fast.

corgi dog carried by vet
Image Credit: Juice Flair, Shutterstock

Some Smaller Breeds Shouldn’t Fast

Some smaller breeds require small frequent meals to keep up their energy levels. Because they deplete nutrients so quickly, fasting takes a harder toll on their system.

We must remember that small dogs are very unlike their wolf cousins, with generally longer lifespans and higher metabolisms. If you wonder if your dog is an appropriate size for fasting, it’s best to ask your vet before taking matters into your own hands.

Health Conditions Don’t Pair Well with Fasting

If dogs have specific medical conditions, not having regular meals might negatively impact their systems. If your dog has a compromised or weakened immune system, it could mean fasting is unsuitable.

vet examining puppy cockapoo dog
Image Credit: MT.PHOTOSTOCK, Shutterstock

divider 9Importance of Proper Execution

It would help if you always feed your dog according to your vet’s recommendations. If you plan to fast your dog intermittently, your vet might want to run certain tests to ensure all is well before proceeding.

Never fast your dog longer than directed. Letting your dog go too long between meals can have major adverse effects that can easily be avoided.

Can Fasting Cause My Dog to Starve?

If you allow your dog to fast intermittently, they certainly will not starve. But we want to stress the importance of doing it correctly. First and foremost, your dog should have a clean bill of health from your veterinarian to make sure that their state is stable.

During the fasting process, it is still imperative that your dog has a freshwater source available to them. Remember that water is far more important in a canine diet, as dogs can survive days without food.

Doing intermittent fasting with dogs the right way means restricting the number of hours that your dog receives their daily food. Feeding them twice a day within an 8-hour window means they will be fasting for 16 hours, enabling them to get all the health benefits of fasting without going long periods without food.

Divider 7Conclusion

Fasting can help your dog live a healthy lifestyle and get them in touch with their ancestral roots. You might want to target other areas of health, but many bodily systems will undoubtedly benefit.

Now you know your dog can safely intermittently fast with appropriate veterinary guidance. In fact, if you have a healthy adult dog, it’s an exquisite thing to do, as it creates a total body reset.


Featured Image Credit: Pixel-Shot, Shutterstock

Related Articles

Further Reading

Vet Articles

Latest Vet Answers

The latest veterinarians' answers to questions from our database