Can Dogs Eat Mashed Potatoes?

Written By: Gemma Johnstone | Last Updated: July 9, 2020

Mashed potatoes in a bowl

Creamy mashed potatoes are popular around the world (and not just at Thanksgiving!) But can dogs eat mashed potatoes? Or are they unhealthy for our canine friends? Read on to find out more.

Potatoes aren’t toxic to dogs in small quantities. In fact, many modern dog foods contain this root vegetable (although this may not be a good thing – more on that in a moment.) If your dog eats a morsel of plain mashed potato, it isn’t likely to be harmful.

Regular consumption of mash, however, could be bad for dogs. Mashed potatoes are often laden with unhealthy ingredients, such as butter, milk, and cream. There’s also new research to suggest that regular consumption of potatoes can lead to disease of the heart muscle in dogs.

Let’s take a closer look at the potential consequences of dogs eating mashed potatoes.

Are Mashed Potatoes Toxic to Dogs?

Plain mashed potatoes aren’t regarded as toxic for your dog. If the potato is unseasoned, you don’t need to worry if your dog snaffles a little.

That doesn’t mean you should give your dog mashed potatoes on purpose though, especially if butter, milk, or other seasonings have been added. Aside from containing unhealthy fats, many dogs are lactose intolerant, which means they struggle to digest these ingredients. Some mashed potato recipes even include garlic or onion, which are both toxic to dogs.

There’s also little nutritional benefit to feeding dogs mashed potatoes. The potato is a starchy carbohydrate that doesn’t provide the same nutritional value as many other vegetables. Eating a lot could even lead to obesity, as the dog is consuming calories without the same density of vitamins and nutrients.

Arguably, the most compelling reason not to allow your dog to eat mashed potatoes is recent research concerning Dilated Cardiomyopathy (DCM) in dogs. This heart disease affects the muscle’s ability to contract, and eventually leads to congestive heart failure.

DCM has often been linked with a genetic predisposition in certain breeds. New studies, however, are highlighting the potential link between diets high in legumes and potatoes and this disease.

While the research is ongoing, avoiding adding potatoes to your dog’s diet would seem a sensible precaution.

Can Dogs Eat Mashed Potatoes With Seasoning or Butter?

Dogs should only eat plain mashed potatoes. While potatoes are non-toxic in small quantities, the ingredients they are cooked with can be dangerous. Here are a few examples:

  • Mash is commonly cooked with lashings of butter, milk, or even cream. Some dogs don’t tolerate dairy well and find it difficult to digest, which can cause stomach upsets and other health problems.
  • Eating high-fat ingredients, such as butter and cream, can also cause your dog to suffer from pancreatitis. This painful gastrointestinal issue can be life-threatening in extreme cases.
  • Salt is also usually added to mash. Excessive consumption can result in your dog becoming dehydrated. Too much salt can also be an issue for dogs with renal problems.
  • Garlic or onion powder are sometimes added to mash for an extra punch of flavor. Both of these root vegetables are toxic to canines.

If you’re going to occasionally offer your dog a small amount of mashed potato, make sure you give it to them before adding extra ingredients.

Note: Dogs shouldn’t eat instant mashed potatoes (or other human processed foods.) These products often contain unhealthy additives.

Can Dogs Eat Raw Potatoes?

It’s best to avoid giving your dog potatoes, for the reasons given above. If you decide to feed your pet potatoes, however, they should always be cooked first.

Many dogs might not like raw potatoes anyway. But, for pooches who are less picky about their foods, a hard raw potato could be a choking hazard.

Potatoes are also part of the nightshade family. These plants contain a glycoalkaloid poison called solanine, which is toxic to both humans and dogs.  

Solanine is mainly present in the green skin, plant leaves, and sprouting green roots of a potato. Peeling green skin before cooking can reduce the risk, but for very green potatoes, it’s best to get rid of them.

Although your dog would have to eat a lot of green potatoes for it to be a problem, solanine can result in severe gastrointestinal issues.

Does Mashed Potato Provide Nutritional Benefits to Dogs?

If your dog is eating a high-quality and nutritionally complete dog food, they should already be getting the right balance of nutrients for optimal health. Adding potatoes isn’t necessary and could have negative health consequences. 

There are a few potential nutritional benefits to dogs eating potatoes though. These include:

  • Dietary Fiber. Providing your dog doesn’t consume excessive amounts, fiber can promote healthy digestion and bowel movements. It may even help to lower cholesterol levels.
  • Vitamin B6. Because it can improve skin barrier function, B6 is often used to help treat dry and flaky skin. There’s even some evidence to suggest it could have a calming effect on anxious dogs.
  • Potassium. This vitamin can help to promote a healthy heart rate, along with improved nerve function, blood pressure and joint health. It’s also beneficial if your dog is suffering from kidney disease.
  • Vitamin C. Unlike humans, dogs produce Vitamin C naturally. While it shouldn’t be over supplemented, a little extra from some potatoes could help your dog to maintain a healthy immune system.
  • Energy Source. Starchy carbs, such as potatoes, aren’t something a dog needs to thrive. But they can sometimes be useful to bulk up a diet, as they’re easy to digest and a good energy source.

When you introduce any new food to your dog’s diet, it should always be done gradually. This allows you to monitor for any signs of allergies or intolerances.

Food allergies commonly result in itchy and irritated skin. They can also cause stomach upsets and, in severe cases, respiratory issues. If your dog has a reaction to any food, you should contact your vet immediately.

Summary

White potatoes aren’t toxic to dogs. Consequently, offering your dog a small amount of plain, unseasoned mash potato as an occasional treat shouldn’t be a problem.  

Make sure, however, that the mash doesn’t contain seasonings or high-fat dairy.

Feeding your dog potatoes as a regular part of their diet isn’t recommended. This starchy carb can cause rapid weight gain. There’s also emerging research about the risk of dogs developing heart disease when it’s fed in high quantities.

About the Author

Gemma is a freelance writer and official dog nut. With 15 years of experience in the pet industry, she is a passionate animal welfare advocate. She has worked for the Scottish Society for the Prevention of Cruelty to Animals, ran her own specialist dog shop for ten years, has volunteered for her local rescue shelter, and is studying towards completing an Advanced Diploma in Canine Behaviour. Gemma is currently travelling around Europe with her wonderful rescue dog, Annie.