Even if you don’t have a dog, you probably know that they can’t eat chocolate; it’s one of the most well know toxin substances for them. But just what is it about chocolate that is so toxin to dogs? Why can’t dogs eat chocolate when we eat it all the time without incident? It come down to theobromine, a chemical in chocolate that humans can digest easily but dogs cannot. “They just can’t break it down as fast as humans and so therefore, when they consume it, it can cause illness,” Mike Tropper, president of the American Veterinary Medical Association, tells Mental Floss. The toxin effects can range from a mild upset stomach to seizures, heart failure, and even death. If your dog does eat chocolate, they may get thirsty, have diarrhoea, and become hyperactive and shivery. While cats are even more sensitive to theobromine, they ‘re less likely to eat chocolate in the first place. They’re much more picky eaters, and some research has found that they can’t taste sweetness Dogs, on the other hand, are much more likely to sit at your feet with those bug, mournful eyes begging for a taste of whatever you’re eating, including chocolate. They’ve also been known to just swipe it off the counter when you are not looking. If your dog gets a hold of your favourite candy bar, it’s best to get them to the vet within two hour, where they are already familiar with your dog’s size, age, and condition. They can give you the best advice on how toxic the does might be and how urgent the situation is.