You may want to sneak your dog little bits of food while you make dinner or dessert, but that doesn't mean that it's a good idea. You can safely give your dog many "human" foods, like carrots, peanut butter, cheese and even raw chicken, but many can cause organ damage, irritation and overall nutritional complications.
Overall Poor Nutrition
When feeding your dog human food, the biggest concern is nutrition and obesity. Human foods are made with human nutrition in mind, not your dog's. Big no-no's include baby food, caffeine, human vitamin supplements, milk, salt and desserts. The onion powder that may be in baby food is toxic to your dog (as onion and garlic in all forms are), whereas caffeine can cause heart and nervous system problems. Human vitamins can damage the lining of your dog's stomach and digestive tract. Milk can cause diarrhea, and salt can cause an electrolyte imbalance. Cake, cookies and other sweet snacks can cause fat to build, which can turn into obesity concerns, diabetes and organ complications.
Human food doesn't affect our dogs as it does us, and some foods can cause organ damage. Foods that contain artificial sweeteners can cause liver failure. A toxin in grapes and raisins can cause damage to the liver and kidneys, and persin—a toxin in avocados—can cause severe congestion and fluid buildup around the heart. When you feed your dog fat trimming on a regular basis, you increase his risks of pancreatitis, and if you offer large amounts of onion, irritation in the gastrointestinal tract may develop.
Obstructions and Lacerations
A lot of foods can cause obstructions in the gastrointestinal tract, as well as internal lacerations. The most common hazard is feeding your dog cooked bones, because they splinter or shatter when your dog chews on them, which can cause lacerations and blockages. If your dog swallows large chunks of food without chewing, the food can get stuck and cause a blockage; for example, fruit pits and seeds can cause blockages if your dog swallows them. Yeast can tear the lining of the stomach and intestines.
Many foods should not be fed to dogs in any amount, as they can cause irritation and complications that may even lead to death. Alcohol can put your dog into a coma, and the hops in beer can cause your dog to pant heavily, run a fever, have seizures and die. Mushrooms can cause toxicity, shock and death. Raw fish can cause a thiamine deficiency, which can result in seizures and sometimes death.