Chocolate. Cocoa ambrosia. That sweet, sweet devil's doodoo. Chocolate contains the compound theobromine, which is toxic to dogs. I think I might name my firstborn son Theobromine one day. But really, chocolate can cause vomiting or even death in pups, so don't let them have it no matter how much they beg.

Avocados are a beautiful thing, especially when converted to guacamole, one of nature's most precious natural resources. However, every part of an avocado (the skin, the nut, and that beautiful gooey green stuff) contains persin. When dogs eat persin, it can cause breathing issues, diarrhea, and vomiting. Not a good time.

Maybe your pup looks a little tuckered out, and needs a pick-me-up. Maybe you just love watching your dog do human things. I don't know why you would give your dog coffee. I'm not you. But do NOT feed your dog coffee, because even though it may be your lifeblood, it's basically poison to dogs. 

Even just a few macadamia nuts – whether they're raw or roasted – can make a dog sick. Symptoms include vomiting, muscle tremors, and even paralysis. 

DO NOT FEED YOUR DOG GRAPES. Even a small amount of grapes can be fatally toxic for dogs of any size, age, or breed. Weirdly, nobody knows what chemical in grapes is the culprit. Science has its limits, I guess.

Not a lot of people know this, but raisins are actually just dried grapes. When I first heard that I was like "whaaaaat?" but I promise you, it's true. Raisins, like grapes, are highly poisonous to dogs. 

The casing of apple seeds contains a natural chemical called amygdlin, which releases a small amount of cyanide during digestion. You've probably heard that it is not particularly wise to eat cyanide. It would take a lot of apple seeds to have a harmful effect on a dog, but make sure to remove the seeds if you plan on feeding your dog a tasty red delicious. 

Ahhhhhhhh, blessed alcohol. Great for you (in moderation). Very bad for your dog (even in moderation). No amount of alcohol is safe for your little floofer. In dogs, alcohol can cause gastrointestinal issues, difficulty breathing, coma, and even death.

The peels, leaves, stems, and fruit of citrus plants contain citric acid, which can cause central nervous system depression if your dog eats enough of it. A little bit of citric acid probably won't do much more than give your dog a tummy ache, though. Even so – best not to risk it.

Like citrus, small amounts of coconut products probably won't cause too much harm to your dog. However, enough fresh coconut can cause a stomach upset and diarrhea. Coconut water should never be given to your pet, as it is high in potassium. You know the old saying – "Dogs and potassium don't mix!"

Dogs don't possess enough of the enzyme lactase, which breaks down lactose. Milk, yogurt, and processed cheeses all contain lactose, so they will do a real number on your dog's stomach if ingested. Doggie farts, anyone?

I know that raw eggs look super delicious and you just wanna chug down three dozen right now, but raw eggs can contain Salmonella and E. coli – which are bad for both dogs and humans. Raw eggs also contain an enzyme called avidin, which is dangerous when ingested by dogs for complicated and mysterious reasons that I do not fully understand, because I didn't fully finish my research on this one. 

Like raw eggs, raw meat can contain dangerous bacteria. It's probably ok to throw your dog a cooked steak every now and then, though. It's also probably ok to throw a cooked steak to a guard dog to distract it, just like in the movies. 

Some salt makes your dog thirsty. Excessive salt can cause sodium ion poisoning. Avoid giving your dog too many salty snacks like pretzels and potato chips. 

Xylitol is a sweetener used in gum, baked goods, candy, and some toothpastes. It can cause liver failure in some pet species. Avoid leaving xylitol products laying around where your dog can get into them!

Yeast dough can rise in your pet's digestive system, causing a great deal of gas. But this doesn't just mean harmless stinky farts! It can cause painful stomach bloating or even twisting, which can become a severe life-threatening emergency. The yeast can also produce ethanol in your dog's stomach, leading to doggie drunkenness (which we've already discussed is dangerous).

If I eat onions, I get heartburn. If your dog eats onions, it might get gastrointestinal irritation that could lead to red blood cell damage. Neither are fun.

Same deal as onions.

Same deal as garlic and onions, ya feel?