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Popcorn & 7 Other Foods That Are Surprisingly Dangerous To Dogs

If you've ever had a dog, you know that most of them will eat just about anything: garbage, rocks, shoes, entire articles of clothing (though they'll inexplicably turn their noses up at actual dog food). Unfortunately, many of the things dogs are willing to put in their mouths aren't good for them — and I'm not just talking about your favorite underwear, either. Quite a few actual food items can be hazardous for your canine to consume, and some of the most dangerous foods for dogs might take you by surprise.

Even people who've never cared for a dog in their lives would probably think twice before letting one eat something like a flaming hot pepper. But certain seemingly benign snacks (including stuff safe enough for the average toddler) could make your pet seriously sick. And the more he eats of the offending food, the worse off he could be.

"If your dog eats a chocolate chip cookie or a piece of moldy bread, chances are he will be perfectly fine (although he may need to go outside to vomit)," explained Petfinder.

However, if your dog is anything like my last dog, a more realistic scenario would involve eating an entire batch or chocolate chip cookies or loaf of moldy bread. (Dogs are smart, but not always that smart.) In that case, Petfinder advised, you should get your dog to the vet right away.

To make sure your dog stays healthy (and save yourself who knows how much money in bills from the vet), it's best to keep all of the following foods out of his reach at all times.

1Chocolate

You've probably heard chocolate is off-limits for pups, but why? Chocolate contains methylxanthines, which can cause "vomiting and diarrhea, panting, excessive thirst and urination, hyperactivity, abnormal heart rhythm, tremors, seizures and even death," according to the ASPCA.

The darker the chocolate, the more dangerous it is: White chocolate contains the lowest levels, while baking chocolate contains the highest. (I once knew a dog who regularly ate Oreos with no problems but almost died after getting into a box of Valentine's chocolates.) Coffee contains methylxanthines, as well.

2Raisins

While you're probably used to thinking of grapes as choking hazards for toddlers, grapes (and raisins) are toxic for dogs, according to PetMD:

"Although the exact substance that causes the toxic reaction is not yet known, dogs should not eat grapes and raisins because even small amounts can prove to be fatally toxic for a dog."

3Onions

From sandwiches to chili to omelets to a million other dishes, onions are in practically everything. Unfortunately, they happen to contain a toxic principle known as N-propyl disulfide, warned the American Kennel Club, a compound which causes a breakdown of red blood cells in dogs, leading to anemia.

And it's not just onions, either: Everything in the allium family (garlic, shallots, leeks, and chives) has the same compound.

4Macadamia Nuts

Macadamia nuts are pricey, so you probably wouldn't be giving them to your pup on purpose anyway. But just in case he breaks into a hotel mini-bar or something, you should know that dogs who eat macadamia nuts "commonly experience weakness in the back legs, vomiting and diarrhea," according to the ASPCA Animal Poison Control Center (APCC).

While most of these cases are mild, some require veterinary care.

5Lemon

Despite the popularity of those videos with dogs tasting lemons, the citrus fruits aren't good for canines, as Rover reported. Lemons and limes contain psoralen compounds and aromatic oils that are toxic to dogs and can upset their stomachs. Interestingly, oranges are usually okay for dogs to eat, though not in large quantities.

6Dairy

Dairy isn't toxic to dogs, which is a good thing considering how skilled they are at stealing licks of ice cream or entire slices of pizza. That said, "Each dog's tolerance for dairy is unique," licensed veterinarian Dr. Rachel Barrack told The Dodo.

"Some can happily lap up a bowl of milk without the slightest issue, while for others, even digesting a small piece of cheddar will come with unpleasant gastric distress."

Better safe than sorry!

7Popcorn

Another food that's in the "choking hazard" category for toddlers, popcorn itself is actually okay for dogs, according the the AKC; in fact, it's nutritious (popped corn kernels contain magnesium, manganese, phosphorous, and zinc, among other things). The problem is all the stuff we put on popcorn. Butter, oils, salt, and other toppings can lead to intestinal upset in dogs, while the fats in oil and butter can contribute to obesity.

8Xylitol

A sweetener that can be found in everything from gum to sugar-free candies to baked goods to low-calorie beverages, xylitol is quickly absorbed into a dog's bloodstream, "resulting in a potent release of insulin from the pancreas," VCA Animal Hospitals explained on its website.

"This rapid release of insulin causes a rapid and profound decrease in the level of blood sugar (hypoglycemia), an effect that occurs within 10-60 minutes of eating the xylitol. Untreated, this hypoglycemia can be life-threatening."