Can Dogs Eat Tomato Sauce? (Watch Out for These Ingredients)

Tomato sauce is perfect on pizza, pasta and breadsticks and is a popular pantry staple. But is it safe for your canine friend?

Like ketchup, tomato sauce isn’t toxic, but it can include ingredients that are not safe for dogs.

Garlic, onion, salt, pepper, oregano, basil, red pepper and sugar are often used to flavor marinara sauce, so it’s best to consider each ingredient on the label.

Garlic and onion are the most concerning, since they can be toxic to dogs – especially for small dogs or eaten in large doses.

Onions and garlic, of the same plant family, contain thiosulphate, which can destroy a dog’s red blood cells, leading to anemia or death.

If ingested, immediate symptoms might include vomiting, diarrhea, abdominal pain and weakness.

Other symptoms can take a few days to show up, including lethargy, pale gums and weight loss.

If these appear, take your dog to see your veterinarian as soon as possible.

Sugar, salt and crushed red pepper are less-concerning ingredients, but should be taken into consideration.

Dogs are sensitive to sodium and too much can lead to sodium poisoning.

And too much sugar isn’t good for anyone – two or four legs – and can lead to obesity and heart problems.

As with ketchup, it’s worse for dogs to have the artificial sweetener xylitol, which can be toxic. Even small amounts can be lethal.

The crushed red pepper is one to watch for because it’s spiciness can cause an upset stomach for your dog.

If your dog ingests small amounts of tomato based spaghetti sauce with toxic ingredients, it might not be a dire situation.

Toxicity levels are dependent on the size of your dog and the amount consumed.

Large dogs are not likely to develop any serious side effects from eating a little bit of tomato sauce, while smaller dogs – under 10 pounds – may become sick from small amounts.

If your dog has consumed a large quantity for his size, it would be best to contact your veterinarian to see what symptoms to watch out for or have them be seen.

Are Tomatoes Bad for Dogs?

Red, ripe tomatoes are safe for your dog to consume in moderation.

Tomatoes are known for containing lycopene, an antioxidant that works against cancer, oxidative stress and other diseases in humans and our four-legged friends.

Tomatoes also contain healthy doses of vitamins A, C, B6 and B3, potassium, manganese, fiber and phosphorus – all of which aid in proper bone health for humans and dogs.

But, do all these good things outweigh the bad?

There are things to take caution about with this delicious plant.

Tomatoes are members of the nightshade family (Solanaceae), along with tobacco, eggplant, potatoes and tomatillos.

These plants contain several dangerous alkaloids.

Tomato plants contain a chemical called alpha-tomatine, which is concentrated in the plant’s green portions, including their leaves, stems and vines.

The amount of tomatine in a tomato decreases as the fruit matures.

So, the riper and redder the tomato, the safer it is for your dog.

Veterinarians agree that while your dog would need to ingest a massive quantity of tomato plants (including the green portions) for the toxin to cause problems, it’s best to refrain from offering it to your friend.

Even if your dog eats the ripe, red part, tomatoes can cause digestive upset to those dogs with sensitive stomachs.

It’s best to keep your dog’s diet sensitivities in mind when thinking about letting him try a tomato.

Tomatoes are also known to cause inflammation in some humans and animals.

If your dog has arthritis or another inflammatory response condition, it may be best to avoid tomatoes.

Side Effects of a Dog Eating Tomatoes

If your dog manages to consume a large amount of the toxin-carrying green parts of red tomatoes and/or unripe green tomatoes, you need to become a faithful observant of his actions to see if a visit to the veterinarian is necessary.

Even though it’s rare, a tomatine toxication can be fatal.

Watch out for following symptoms:

  • Drooling
  • Diarrhea
  • Vomiting
  • decreased heart rate
  • tremors and seizures
  • loss of coordination/weakness
  • irregular heartbeat
  • lethargy
  • dilated pupils
  • paralysis

While these signs are rare, and your dog should be in ok health if he eats a small amount, it’s a good idea to keep a watchful eye on your dog and keep your vet informed of any out-of-the-ordinary symptoms.

Take your dog to your vet immediately if he was able to get into your garden – or a neighbor’s – and ate a large dose of plants.

And, it’s probably safest – for your dog and your tomatoes – to fence off your garden or keep your dog supervised on outdoor visits.

Can Dogs Have Ketchup?

Ketchup is not harmful to dogs.

Since the toxins in tomatoes are found in the leaves and stems of ripened tomatoes and green, unripe tomatoes, most commercial ketchups are fine for dogs to eat.

The most-used tomato-based kitchen staple is ketchup.

From burgers and hot dogs, to french fries and hash browns, to eggs – ketchup is the perfect condiment for many of us two-legged creatures.

If you love to put ketchup on everything, it’s a safe bet your dog will want some at some point.

We know ketchup isn’t a health food, but is it harmful for your four-legged friend?

Even though most ketchups do not contain toxic substances to shy away from, ketchup is generally not recommended for dogs because it’s nutritionally empty, highly processed, and full of questionable ingredients like sugar and salt.

You might think organic ketchup is a safer bet than the standard variety, but those labels need to be checked for harmful add-ins.

After tomatoes, oftentimes the second ingredient of ketchup is some form of sugar, including high fructose corn syrup and corn syrup.

All this sugar can add up – which isn’t good for your dog’s overall health.

Too much sugar for dogs can lead to all the same health problems us humans have – obesity, diabetes, heart issues.

But that doesn’t mean the sugar-free varieties are safe! In fact, they can be worse for your dog.

Xylitol, a popular artificial sweetener, causes a major insulin release in dogs, which can cause low blood sugar, kidney damage, vomiting and/or weakness.

Some ketchup varieties include flavorings and spices, including onion powder, cinnamon, garlic, allspice and extra salt – all of which are not good for your furry friend.

Dogs have a low salt tolerance and salt poisoning - hypernatremia - can cause permanent organ damage and even death.

Hypernatremia symptoms can include loss of appetite, stumbling, diarrhea, vomiting, extreme thirst, excessive urination, swelling, kidney problems, seizures, low energy.

It’s best to stay away from flavored ketchups that are spicy, because these may contain toxic ingredients as well.

Ketchup packets from fast-food restaurants can pose a greater danger.

These are loaded with even more chemical preservatives than the store-bought variety, and your dog might be tempted to eat the entire packet – plastic and all!

Be sure to keep any of these packets out of your dog’s reach.

You can take into consideration your dog’s size – the larger the dog, the more they’re probably able to tolerate the sugar, salt, and additional ingredients and flavors – but less or none is always better.

Unfortunately, you won’t know whether your dog is allergic to any of the ingredients in ketchup unless he consumes some, so it’s better to be safe than sorry.

If your dog eats a little ketchup, keep an eye out for any out-of-the-ordinary symptoms. If she ate a lot, a trip to the vet may be necessary.

And remember that this condiment staple is junk food and should be treated as such.

Can Dogs Eat Tomato Soup?

There is nothing in tomato soup that is toxic for your dog.

While some varieties may include garlic and onions, the amount is not enough to cause much worry.

Some tomato soups may include cheese and/or cream.

While dairy itself isn’t harmful to dogs, some dogs are lactose intolerant, so eating cheese can cause an upset tummy.

With any of these added ingredients take your pup's size into consideration, how much soup she consumed, and any out-of-the-ordinary symptoms, including vomiting, diarrhea, reduced appetite and lethargy.

Let your veterinarian know if these symptoms persist or if your dog experiences sticky and pale gums, a fever, blood in his stool or vomit, and a swollen abdomen.

Wrapping it pUp...

We love our dogs and want to give them everything their hearts desire.

But if your furry friend is begging to slurp up some pasta sauce, it’s best to think twice about letting him take part in that fun.

While small quantities of red, ripe tomatoes and their many varieties here and there is not harmful, consuming too many tomatoes – and even worse the tomato plants – can cause more problems than it is worth!

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