It’s not at all uncommon for a dog owner to slip his or her pet a little human food once in a while. After all, we love our pets and want them to be happy.

Of course, while the occasional treat is typically harmless, dogs that eat the wrong things can sometimes develop serious health problems.

Here are seven bad, toxic foods for dogs that you might not have been aware of.

1. Onions

onions toxic dog foodAn onion is a potent vegetable. It can bring tears to your eyes when you slice one. But onions can do far worse to your dog. In some severe instances, they can even be fatal.

Onions can damage your dog’s red blood cells so they can’t deliver oxygen throughout the body. When a dog develops anemia due to a lack of blood cells, that can even be deadly. Symptoms of onion toxicity include weakness, lethargy, a lack of coordination, vomiting, and diarrhea. Reddish or brownish-colored urine may also occur. If this happens, get your dog to the vet as soon as possible.1

2. Chocolate

chocolate bad for dogsHow can something that tastes so good be so bad for a dog? Unfortunately, chocolate is one of the most toxic types of human food for canines.

The reason has to do with a chemical found in chocolate known as theobromine. It’s used in medicine as a muscle relaxant and heart stimulant. But it’s toxic to dogs because their digestive systems are unable to metabolize the chemical.2

The amount of theobromine that’s toxic to a dog depends on the type of chocolate. In general, the more bitter and darker the chocolate, the more of the chemical it contains.

For example, one ounce of chocolate used in baking contains anywhere from 130-450 mg of theobromine. The milk chocolate found in candy bars only has about 44-58 mg per ounce. White chocolate barely registers on the theobromine scale. It has a mere .25 mg an ounce. If your dog is medium size (around 50 pounds), he or she would have to eat about an ounce of baking chocolate or nine ounces of milk chocolate to have problems.3

You usually don’t need to be concerned if your dog happens to snag a small portion of a chocolate bar. If you have a small dog who eats some chocolate, however, you need to watch him or her carefully regardless of how much was consumed. But if he or she ingests a substantial amount, that could lead to major problems.

Some dogs with chocolate poisoning will have diarrhea and vomiting as well as an increased thirst. They may also pant and act restless. If your dog ate chocolate and starts to show these signs or others (such as seizures or muscle tremors), go to the vet immediately.

Chocolate poisoning can be fatal in extreme cases.4

3. Grapes

Grapes might seem harmless, however, they can be anything but healthy for your pet. Sure, they’re good for humans, but they can cause lethargy, weakness, stomach pain, and diarrhea in dogs, as well as appetite loss.5 Grapes can even lead to kidney problems.

And the scary part is that these symptoms can come on suddenly. Stay on the safe side and make sure you keep grapes out of your dog’s reach. The same thing goes for raisins (which are just dried grapes), which can cause the same health issues as can grapes.6

4. Avocado

avocado bad for dogsAvocados are a delicious (and healthy) human food, but for dogs they can lead to big problems. If a dog eats the pit of an avocado, that can lead to choking or an intestinal obstruction.7 So, keep your pup away from your avocado tree.

5. Bread Dough

If you like to bake your own bread, you need to be very careful if you have a dog. Unbaked dough can be toxic, leading to a potentially fatal condition known as gastric-dilation volvulus, or GDV. Some people call this “bloat.” However, while a bloated stomach can lead to GDV, it doesn’t automatically result in GDV. The reason GDV is so severe is that it causes the stomach to twist, or flip. This shuts off not only the entrance to the stomach but the exit as well.8

But that’s not the only risk. If your dog eats bread dough, it will continue to rise inside of his stomach, distending the organ. It will also release ethanol into a dog’s bloodstream, which can be poisonous. Get to a vet immediately if your dog has consumed any uncooked dough.9

6. Corn on the Cob

Corn is OK for your dog, but corn on the cob is not. A dog can easily choke on a cob or suffer an intestinal blockage. Problem signs include vomiting, diarrhea, loss of appetite, lethargy, and dehydration.10

7. Milk

milk bad for dogs

If cats can drink milk with no problem, why can’t dogs? Well, some dogs (just like humans) are lactose intolerant. This means their bodies don’t have lactase, the enzyme needed to be able to break down lactose. This is a sugar that is found in milk.11

Unfortunately, you won’t know that your dog has lactose intolerance unless he or she has already been diagnosed by your vet. Stay on the safe side and keep milk away from your pooch.

A Final Word

You won’t need to panic if your dog happens to eat a small bite of chocolate, onion, or most of the other foods listed above. But if your pet consumes a large quantity of any of these foods, get her to the vet as quickly as you can.

More tips on what’s ok and what’s not ok to feed your dogs:

Can I Give My Dogs Cranberries? Are They Safe?

Ginger for Dogs? 4 Ways It Can Improve Your Dog’s Health


DisclosureThe ActivatedYou team creates these articles as a way to provide you with the latest information on health and nutrition. Unfortunately, we cannot make specific product recommendations for our website visitors, such as “Dr Marty Nature’s Blend” or “ProPower Plus” Please consult with your healthcare provider to determine the best products for you.