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Learn : Food Transition & Vomiting

How Can I Help My Dog through a Tricky Food Transition?

Dog with an upset stomach

You’ve decided to switch to a fresh diet because you know it will improve your dog’s energy level, skin, and coat, digestive function, and promote a healthier and happier life for your pet. Then why is he having a digestive upset? With an appropriate transition, some patience, and a little vigilance, you can overcome the challenges that accompany any diet shift and begin to reap the benefits of a healthier diet plan.

Why is My Dog Having Digestive Upset?

Canine health is largely driven by an individual’s microbiome. Your dog’s microbiome is the culmination of a variety of bacteria and other microorganisms that live in and on your dog. No need to worry; these bacteria are perfectly normal and actually facilitate many of your dog’s bodily functions.

The microorganisms that make up your pet’s microbiome boost immune function, affect his emotional well-being and help him properly digest his food. The bacteria in your dog’s gut produce enzymes, unique proteins that enable him to glean the nutrients he needs from his new, fresh diet

Your dog’s stomach and digestive microbiome needs time to adjust to switching to new food from old food, and fresh food is no exception, which is why few recommend going completely cold turkey from his old diet when making the switch. A fresh diet contains novel nutrients and ingredients that require a shift in your pet’s microbiome to be properly digested and utilized. After your dog has had time to adjust, you should begin to see a positive change in his overall body condition and attitude.

Other Potential Factors

Your dog’s food may not be the only change in his life. Dogs experience digestive issues for a variety of reasons, and it is important to consider other factors that may be impacting your pet’s health. Many dogs and puppies react physically to new stressors, such as a new baby or a move. Some experience side effects to medications that may mimic the symptoms discussed below. It is important to talk to your veterinarian about other potential changes if symptoms persist. 

What Symptoms Might I Encounter?

Transitioning your dog to fresh dog food has a myriad of positive benefits for their digestive health, but pet parents may notice symptoms that accompany any change in diet. Many of these symptoms are the most noticeable in the first weeks.

Some of these initial changes may be positive; your dog or puppy may become more excited for mealtimes or beg more enthusiastically for dinner. This is normal, and he is still receiving the calories and nutrients he needs. He simply appreciates his exciting, tasty new diet. However, certain changes may be a cause for concern for pet parents.


Pet parents transitioning to fresh food may notice changes in their dog’s poop consistency during the first week or so. While some may have firmer stools, some may experience diarrhea and need to go more often, another product of an adjusting microbiome.

You may also notice changes in poop color, another typical response to a new, fresh diet. Ingredients in your dog’s food that affect the color in his pet food may also change the color of his stool, which is completely normal and to be expected. However, if your pet experiences dark bloody stool or diarrhea that lasts longer than three days, you may want to contact your veterinarian about strategies for a happier digestive transition.


Your puppy’s new diet contains a higher fat content than many commercial kibble dog foods. Each recipe is carefully formulated to include healthy fats and oils that promote coat health and facilitate growth in your pet. Unfortunately, this positive change is still just that, a change. Vomiting may be a response to nutrients your dog may not be used to in his previous food.

Vomiting once or twice is normal for a dog transitioning to fresh food, but pet parents should consider taking their dog to the vet if the vomiting is persistent, severe, and lasts longer than three days.

Pet parents can also try a brief fast to help their dog’s digestive system adjust to his new food. Dr. Justin Shmalberg recommends a 12 to 24 hour fast followed by reintroducing your dog’s fresh diet one half meal at a time, allowing your his microbiome time to reset. Following the transition guide provided may help pet parents avoid some of the pitfalls of a new diet.

Be aware, that with the introduction of any new food, your dog may show extreme excitement through the sheer speed in which the food is being eaten. Since fresh dog food is very palatable, you should find that pets will devour the food quickly. This inhaling of food can cause regurgitation. This does not mean your dog is having a negative reaction to the food, however, it just means that alternative feeding mechanisms may need to be incorporated to help manage the feeding process.  Look into puzzle feeding bowls to help slow down the eating process.

A Decrease in Appetite or Not Eating

Most dogs appreciate the flavor and freshness of their new food. However, some pets are picky eaters and may be unsure of a novel diet. Most should eventually enjoy the benefits of a fresh diet and find mealtimes more exciting than ever. They may prefer a different recipe or protein source.

If your pet seems uninterested in eating regardless of recipe, other factors may be at play. Stress, sudden changes, treats, or medication may be affecting his appetite. Underlying conditions may also influence his appetite. If you switched to a fresh diet due to a pre-existing condition, be sure to speak with your veterinarian if your pet is not eating. The condition may not be well-controlled and could cause nausea or food-aversion, even on the best of regimens. Try remaining consistent about feeding your dog at designated meal times. With a little patience and the right recipe, most pets thrive on a fresh meal plan.

What Can I Do?

There are many steps you can take to make your pet’s transition a smoother one. A bland diet may help give your dog’s gut bacteria the time it needs to adjust to his new food. Try mixing half of your dog’s NomNomNow meal with an equal portion of rice or potato.

You can also try a temporary fast to help your dog’s digestive system reset. Pull food for 12 to 24 hours, then try giving your dog half a meal. Remember to limit treats and other goodies during his transition and to plan around any medications.

When Should I Go to the Vet?

Although some vomiting, diarrhea, constipation, and appetite changes are to be expected initially, persistent symptoms or symptoms accompanied by lethargy are not normal. If your pet is vomiting or has diarrhea for more than three days, you should talk to your vet about your transition.

Every pet is unique, and their transition may be too. Your dog’s age, previous diet, and other health conditions may affect his adjustment to a new, fresh diet. Remember to mention any other life changes to your vet, including everything from a new dog park to a new flea medication.

If your dog suffers from a serious medical condition, such as advanced kidney disease or pancreatitis, they may require a more stringent diet, and NomNomNow may not be the right fit. Remember to consult your veterinarian before changing his diet.

Most pets should find themselves feeling better than ever after an appropriate transition to a fresh diet. In the meantime, your vet may be able to suggest strategies specific to your dog that allow him the healthy, happy transition he deserves.

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