How Long Does It Take for a Dog to Digest Food? Fact Checked By Vet

If you're a dog owner, you've probably wondered about the intricacies of your furry friend's digestive system. Understanding how long it takes for a dog to digest food is not only intriguing but can also have practical implications for their health and wellbeing.

In this guide, we'll delve into the world of canine digestion, exploring the various factors that influence digestion time and how to ensure your dog's digestive system functions optimally.

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How Long Does It Take for a Dog to Digest Food?

Before we delve into the details, I’m sure you want the simple answer to this question, short and sweet. Well, here it is, although it’s not as straightforward as one might hope. The information you’ll most often see cited on the internet is: digesting food usually takes somewhere between six to eight hours for dogs (1).

But, this actually only refers to the time it takes for the food to leave your dog’s stomach. This is called “gastric emptying time” or GET in scientific literature. The actual time that passes from the moment your dog eats until they poop (called total transit time - TTT) is actually anywhere between 18 and 55 hours (2).

Sounds kind of complicated, right? So let’s take a moment to try and understand the digestive system of our canine companions.

Canine Digestive System: A Brief Overview

The process of digesting food in dogs begins the moment they take their first bite. Unlike humans, who start digestion in the mouth through chewing and enzymatic action, dogs primarily use their teeth for tearing and crushing food. The real action begins once food enters the stomach.

Stomach Digestion

A dog's stomach is designed to handle a wide range of food types, from meat to vegetables. The stomach's acidic environment plays a crucial role in breaking down proteins and sterilising potential pathogens in the food. This stage can vary in duration, but on average, it takes about five to eight hours for the stomach to complete its job.

Small Intestine: The Main Digestive Hub

The partially digested food then moves into the small intestine, where the majority of digestion and nutrient absorption occurs. The small intestine in dogs is quite long, measuring about two and a half times their body length. This impressive length allows for more surface area for nutrient absorption. The duration spent in the small intestine can typically  range from 1 and a half to four hours (2), depending on factors such as the type and quality of food.

Large Intestine: The Final Stretch

After the small intestine, the remaining undigested food, and waste products enter the large intestine or colon. Here, the focus shifts from digestion to absorption of water and electrolytes. This stage is called large intestinal transit time and can take quite a long time (up to 40 hours and more according to the studies I read during my research).

Factors Influencing Digestion Time

Now, not only is the dog’s digestive system quite complex, but there are also numerous factors that can affect how quickly they digest food. These are the most important ones:

#1 Size, Age, and Breed of Dog

The size, age, and breed of a dog play significant roles in their digestion process. Generally, smaller dogs and puppies require less food and have shorter digestion times compared to larger, adult dogs. Small breeds and puppies typically take around four hours to complete digestion, whereas larger dogs may take approximately eight hours.

However, research shows that breed size is not always the sole determinant. Some factors, such as genetics, metabolism, and individual variations, can influence digestion times. Age also matters, as metabolism tends to slow with age. Older dogs may require less food and experience longer digestion times.

Furthermore, certain breeds, including Great Danes, Labrador Retrievers, and German Shepherds, are more prone to gastrointestinal issues, which can affect digestion.

#2 Diseases and Health Conditions

A dog's overall health significantly impacts their digestion. Health conditions like malabsorption diseases (e.g., EPI or IBD), leaky gut syndrome, intestinal blockages, cancer, ulcers, parvovirus, gastritis, and colitis can disrupt the digestive process. These conditions can lead to poor nutrient absorption, irregular digestion times, and digestive discomfort.

Maintaining your dog's health through regular check-ups and prompt treatment of any underlying conditions is essential for optimising their digestion.

#3 Activity Level

A dog's activity level also affects digestion. Dogs are evolutionarily designed to handle a raw meat-based diet. Their stomachs can store food for extended periods, allowing for slow digestion to produce energy when needed. Increased physical activity accelerates digestion by moving food from the stomach to the intestines, where nutrients and calories are absorbed. This adaptation ensures that dogs can access energy for physical tasks quickly.

#4 Hydration

Water intake plays a crucial role in digestion. Adequate water consumption softens food, aids in chewing, and enhances the secretion of enzymes and acids necessary for breaking down food. Hydration also ensures that stools remain soft, facilitating comfortable elimination. It's essential to provide your dog with access to clean, filtered, or spring water to support their digestion.

#5 Food Type

The type and volume of food your dog consumes directly affects digestion. Protein content is a significant factor influencing digestion time, with higher protein diets typically digesting more efficiently. Additionally, food processing methods play a role.

Commercial pet foods, for instance, differ in digestion times. Wet dog food, containing higher water content, is generally digested faster, typically within four to six hours. In contrast, dry dog food, with lower water content, may take longer, around eight to ten hours.

Related: How Much Wet Food Should You Feed Your Dog?

Raw dog food is often considered the most digestible option. It aligns with a dog's natural diet and lacks the starchy grains and sugars found in processed foods. Raw food contains live enzymes that aid efficient digestion, resulting in shorter digestion times.

My Final Thoughts

So what’s the takeaway for all of this? Perhaps that dogs are incredibly complex creatures! The average time it takes for a dog to completely digest food is approximately 24 hours, but it could be longer or shorter.

Smaller, younger, and more active dogs digest food more quickly, but that’s not always the case. It’s all individual. If you were hoping you can use this to calculate when your dog will need to poop after they eat, I’m afraid that’s not going to happen.

But, you can still figure out your dog’s rhythm just by watching them - dogs are creatures that love routine and typically love to do these things at the exact time each day.

References

1. PetMD Editorial. September 29, 2017. “7 Interesting Facts About Your Dog’s Digestive System”. PetMD. Retrieved September 5, 2023. https://www.petmd.com/dog/nutrition/7-interesting-facts-about-your-dogs-digestive-system
2. Deschamps C, Humbert D, Zentek J, Denis S, Priymenko N, Apper E, Blanquet-Diot S. (2022). “From Chihuahua to Saint-Bernard: how did digestion and microbiota evolve with dog sizes”. International Journal of Biological Sciences. 2022 Aug 1;18(13):5086-5102. doi: 10.7150/ijbs.72770. PMID: 35982892; PMCID: PMC9379419.