Can Dogs Eat Potatoes - Plant, Plate and the DCM Row

Plain cooked potato flesh is starch, and Merck's nutrition material notes that both dogs and cats digest properly cooked starches with greater than ninety percent efficiency. That is the boring half of this page and it is over in a sentence.

The interesting halves are the parts of the plant that are not the cooked tuber, and the argument about legumes, potatoes and canine heart disease that has been running since 2018 and is still not settled. We are going to take both seriously, and we are going to be clear about where the evidence stops.

The plant, and what the manual actually names

Potatoes belong to Solanum, and Merck's list of plants poisonous to animals gives the entry as: "Leaves, shoots, and unripe berries. Inflammation of the stomach and intestine with bleeding, weakness, excess drooling, difficulty breathing, trembling, progressive paralysis, laying down, death."

Read the first three words closely, because they are doing precise work. Leaves. Shoots. Unripe berries. A potato plant in a vegetable bed is a leafy plant that produces small green fruits which look like tiny tomatoes, and those fruits catch people out every year. Sprouts on a potato that has been in a cupboard too long are shoots.

What that entry does not address is the greened tuber, the potato that has gone partly green on a windowsill. You will find that claim on a great many pages. We could not confirm it from the sources we read, so we are not going to assert it here, and we are also not going to tell you it is fine. If a dog has eaten a green potato, that is a question for the practice, and describing it accurately gets you a better answer than a website guessing on your behalf would.

Solanum entry from the Merck Veterinary Manual, plants poisonous to animals, read 4 August 2026. Starch digestibility from the Merck Veterinary Manual, nutritional requirements and related diseases of small animals, read 4 August 2026.

ONE POTATO, TAKEN APART

  THE PLANT IN THE GARDEN
    leaves ............. named by Merck
    shoots ............. named by Merck
    unripe berries ..... named by Merck (the small green
                         fruits that look like tomatoes)
        -> this is the part with a documented entry


  THE POTATO IN THE CUPBOARD
    sprouts ............ these are shoots
    green patches ...... not addressed in the sources
                         we read. we say so rather than
                         filling the gap
    ordinary skin ...... starch and fibre
    ordinary flesh ..... starch, digested at >90%
                         efficiency once cooked


  THE POTATO ON THE PLATE
    boiled, plain ...... the dull answer
    roasted in fat ..... a fat question
    chips and crisps ... fat and salt
    with butter, gravy,
      onion or garlic ... whatever is on it, not the potato


  THE POTATO IN THE BAG OF FOOD
    an ingredient in some formulations, and the subject
    of an unresolved investigation. see below, and do not
    change your dog's diet because of a web page.

The grain free and heart disease question, stated honestly

This is where people usually want a verdict, and the correct thing to report is that there is not one.

In 2018 the US Food and Drug Administration began investigating reports of dilated cardiomyopathy in dogs eating diets with legumes, pulses or potatoes high in the ingredient list. By its June 2019 update, the FDA had received 524 case reports involving 560 dogs, including 119 deaths, covering January 2014 to April 2019. Its own words at the time: "it is not clear what it is about these diets that may be connected to DCM in dogs."

The current position has not resolved into a verdict. The FDA states that it "does not know the specific connection between these diets and cases of non-hereditary DCM", and describes the condition as one that "may be affected by the interplay of multiple factors such as genetics, underlying medical conditions, and diet". It also makes a point that gets left out of most retellings: "legumes and pulses have been used in pet foods for many years, with no evidence to indicate they are inherently dangerous". The agency has stopped publishing lists of commonly reported brands, noting that several manufacturers have since adjusted formulations.

Taurine comes up constantly in this argument, and the FDA's handling of it is instructive. Taurine deficiency is an established cause of dilated cardiomyopathy, and Merck confirms that taurine is an essential amino acid for cats and that deficiency causes dilated cardiomyopathy and central retinal degeneration in them. But the FDA is explicit that taurine deficiency "is not the only cause of DCM", and the reported canine cases have not resolved into a simple taurine story.

So: a real signal, taken seriously by a regulator, investigated for years, with no established causal mechanism and an explicit statement that the ingredients are not inherently dangerous. Anyone who tells you this is settled, in either direction, is ahead of the evidence.

The potatoes people actually feed

Most of the time the question is not about botany at all. It is a roast potato off a plate, a handful of chips, or crisps from a bowl.

Those are fat and salt questions wearing a potato costume. Roast potatoes are cooked in fat, chips are fried, and crisps are both fried and salted. Merck's salt entry gives the condition that matters: "salt toxicosis is unlikely to occur as long as sodium-regulating mechanisms are intact and fresh drinking water is available." Merck's pancreatitis entry describes dietary indiscretion as a believed rather than proven risk factor, with the miniature schnauzer dramatically over represented.

The fuller treatment of both is on the bacon page for the fat and the ham page for the salt. And if the potato arrived with onion or garlic on it, that is the more urgent question by some distance.

Raw potato as an object

A whole raw potato is a hard, round, indigestible object of a decent size, and a dog that has taken one from a vegetable rack has swallowed something with the wrong geometry. Merck describes foreign bodies as objects that "cannot be digested", are "slowly digested", or are "too large to pass through the GI tract", and notes that "large, round objects often result in complete obstruction". As with all of these, the manual's framing is that outcome is good when the problem is recognised and treated quickly.

What to have ready when you ring

Keep the weight and the numbers in the emergency folder, use before you call the vet for the shape of the call, and the emergency vet finder for the last line.

Questions people actually ask

Should I stop feeding a grain free food?

Not on the strength of this page or any other. The FDA's own instruction is to consult your vet before changing your dog's diet, and it has explicitly said there is no evidence that legumes and pulses are inherently dangerous. Take the question to your next appointment with the actual bag in a photograph, which is a far better conversation than a forum thread.

Is sweet potato the same question?

Botanically no, they are not even in the same family, though sweet potato does appear in the same conversation about diet formulation. The sweet potato page covers it separately.

My dog ate potato peelings from the compost. Anything different?

Two things worth mentioning on the phone: whether the peelings included green areas or sprouts, and whether anything else was in the compost, because compost heaps are rarely single ingredient. Say "compost" rather than "potato" and list what you can.

Are tomatoes related to this?

Same genus, and green tomatoes and tomato plant material raise the same family of questions. The tomatoes page deals with it, and if you are auditing a vegetable patch then the plant reference and the home and garden walkthrough are the practical next step.

Which starches are the unremarkable ones?

Rice is the one people ask about most, and corn is worth reading for the cob rather than the kernel. The whole index is at the food directory.

How we sourced this page

Merck Veterinary Manual, plants poisonous to animals. The Solanum entry naming leaves, shoots and unripe berries, with the signs listed. Read 4 August 2026.

Merck Veterinary Manual, nutritional requirements and related diseases of small animals. Starch digestibility above ninety percent in dogs and cats; taurine as an essential amino acid for cats with deficiency causing dilated cardiomyopathy and central retinal degeneration. Read 4 August 2026.

US Food and Drug Administration, questions and answers on the Center for Veterinary Medicine investigation into a possible connection between diet and canine heart disease, updated June 2019. The 524 case reports involving 560 dogs and 119 deaths between January 2014 and April 2019, and the statement that it is not clear what it is about these diets that may be connected to DCM in dogs. Read 4 August 2026.

US Food and Drug Administration, questions and answers on FDA's work on potential causes of non hereditary DCM in dogs. The statement that FDA does not know the specific connection; the description of multiple interacting factors including genetics, underlying medical conditions and diet; the statement that legumes and pulses have been used in pet foods for many years with no evidence that they are inherently dangerous; the decision to stop updating commonly reported brands; the statement that taurine deficiency is not the only cause of DCM; and the instruction to consult a veterinarian before changing a dog's diet. Read 4 August 2026.

Merck Veterinary Manual, salt toxicosis in animals; pancreatitis in dogs and cats; and gastrointestinal obstruction in small animals. Read 4 August 2026.

Where a claim is common online but absent from the sources we read, this page says so rather than repeating it. The greened tuber is the example on this page.

If it has already happened, what to do when a dog has eaten something is the page to work through while you wait.