25 Dangerous Foods for Dogs Who can resist those big brown eyes and cute doggie grin? Can a little reward from the table or getting into Mom or Dad’s stuff really hurt your dog? Well, that depends on what it is and what's in it. If it contains the sweetener xylitol, it can cause your dog some real problems. In fact, there’s a lot of people food your dog should never eat. And, it’s not just because of weight. Some foods are downright dangerous for dogs -- and some of these common foods may surprise you. Xylitol Candy, gum, toothpaste, baked goods, and some diet foods are sweetened with xylitol. It can cause your dog's blood sugar to drop and can also cause liver failure. Early symptoms include vomiting, lethargy, and coordination problems. Eventually, your dog may have seizures. Liver failure can happen within just a few days.