Beyond chocolate, many people overlook that grapes, raisins, onions, and garlic (and even scallions and chives) can be dangerous to both dogs and cats. Also, foods containing xylitol—a common sugar substitute found in sugar-free gum or baked goods—are particularly toxic for dogs. Non-toxic foods can still cause upset if fed in excess or prepared inappropriately, so a balanced, species-appropriate diet is key. The ASPCA and Pet Poison Helpline websites offer reliable info from experts if you want to dig deeper.