Getty Images/iStockphoto Michael Pettigrew / BuzzFeed 1. Bread Dough Getty Images/iStockphoto Magone Raw bread dough with yeast can be dangerous for all pets. The dough can rise and release gases in their stomach, which could damage internal organs and cause difficulty breathing. Active yeast also produces alcohol, which can cause coma, seizures, or even death. 2. Grapes and Raisins Getty Images/iStockphoto vonEisenstein Grapes and raisins can be extremely toxic to dogs, but not always. One dog might get really sick and develop kidney failure after eating only a few grapes or raisins, but others might not be affected at all. Because you don't know how your dog will react to grapes and raisins, it's best to keep them away from all dogs. There's no sense in risking it. 3. Chewing Gum Getty Images/iStockphoto Eric Brownstone Xylitol is the ingredient used in sugar-free chewing gum to make it sweet, and in dogs, the chemical plays a nasty trick. The dog's body thinks sugar levels are high, so insulin is released and blood sugar drops to dangerously low levels that may cause death. 4. Chocolate Getty Images/iStockphoto Jacek Nowak For pets, "death by chocolate" isn't a delicious life goal; it's a serious concern. Chocolate contains theobromine, which is toxic to both cats and dogs. The darker the chocolate, the higher the amount of theobromine (so milk chocolate is less toxic than dark chocolate), but you should keep all chocolate products out of reach. Depending on how much and what kind of chocolate a pet eats, intoxication can cause vomiting, upset stomach, fever, seizures, and death. 5. Raw Eggs Getty Images/iStockphoto Iryna Melnyk Eating raw eggs isn't a good idea for any animal because they carry the risk of salmonella, but for cats, raw eggs can also cause skin and coat problems. The compound alvidin in egg whites can cause a vitamin B deficiency that results in rough skin and hair loss. 6. Onions and Garlic Getty Images/iStockphoto Teen00000 In cats and dogs, toxins found in onions and garlic can damage red blood cells. Your pet probably won't eat enough fresh garlic or onion to cause serious problems, but onion and garlic powders have concentrated levels of these toxins, which means these products could be more dangerous. In any case, symptoms only develop a few days after ingestion, and serious cases could mean a trip to the vet. 7. Corn on the Cob Getty Images/iStockphoto Valenaphoto Dogs tend to love corn on the cob, but if they chew on it, pieces of the cob can cause extremely dangerous and painful obstruction in the digestive system. This could be very painful for your dog and could even cause death. Cut the kernels off the cob if you want to give them a treat, and make sure to throw out cobs in a closed trash can they can't get into. 8. Wild Mushrooms Getty Images/iStockphoto Olha_Afanasieva When out for a walk, it's best to keep curious pets away from wild mushrooms. Most mushrooms that grow outdoors are safe, but some are poisonous to both humans and pets. So in this case, if you shouldn't eat it, neither should your pet. 9. Alcohol Getty Images/iStockphoto Stepan_Bormotov Think of all of the effects alcohol has on the human body. The same effects occur if your pet has alcohol, but because of their smaller size and differences in metabolism, the effects on their bodies are quicker and more severe. In other words, alcohol poisoning can occur with a smaller amount and result in coma, seizures, or death in extreme cases. 10. Avocado Getty Images/iStockphoto NadiaCruzova Avocados aren't a serious risk to cats and dogs, but they could be deadly to other animals including birds, rabbits, and horses. In these animals, the compound persin can result in difficulty breathing and damage to the heart. Even in cats and dogs, avocados can cause vomiting and diarrhea, so it's best to keep this one away from all of your pets. 11. Caffeine Getty Images/iStockphoto aimy27feb Like alcohol, caffeine causes similar effects on the bodies of cats and dogs as it does on humans. But again, because of their size, the likelihood of a caffeine overdose is higher for pets. Pets who eat or drink anything containing caffeine should be watched closely for symptoms including vomiting, racing heart, and hyperactivity. 12. Macadamia Nuts Getty Images/iStockphoto faengsrikum Many nuts can cause upset stomachs in cats and dogs, and macadamia nuts tend to produce the worst effects. After eating these nuts, pets usually experience a lot of pain and fever for a few days, so it's best to keep these up and out of their reach. 13. Hops Getty Images/iStockphoto ChristianJung Most people probably don't keep fresh hops in their house, but people who have them around for home brewing will want to keep them away from their canine friends. Dogs who eat hops can get very high fevers and even multiple organ failures. 14. Moldy Foods Getty Images/iStockphoto Witthaya Your pet is not a garbage disposal, and spoiled foods can be just as dangerous to your pet as they can be to you. Some molds that grow on foods can be very toxic to your pet and cause extreme, potentially deadly tremors. 15. Milk Getty Images/iStockphoto fotoedu This one is surprising, because most people think that cats LOVE milk. They might like its taste and richness, but most cats are actually lactose intolerant. Giving your cat some milk probably won't cause serious problems, but it could mean an upset stomach and possibly diarrhea — no fun for either of you. 16. Stone Fruits Getty Images/iStockphoto Melpomenem Stone fruits like apricots, plums, peaches, cherries, and nectarines can be a nice treat for your pet, but make sure they don't swallow the pits. The hard "stones" in the middle of these fruits can cause your pet to choke or form a blockage in the digestive tract. Although it's unlikely, the swallowing the pits also carries the risk of cyanide poisoning. 17. Animal Bones Getty Images/iStockphoto ihorga Even though you might have thought that there's no better treat for your dog than a bone to chew on, they can be very dangerous or deadly. Fragments of the bone can become stuck in your pet's digestive system and puncture or tear its lining. This could mean an emergency trip to the vet, and if the internal injuries cause a bacterial infection, even death.