Peanut Butter: Is a favourite for many dogs. Not only is it a good source of protein but it also contains heart-healthy fats and vitamins. Choose natural peanut butter for your dogs (and your children!) and preferably, one without added sugars and other additives. Similarly, bananas are a great treat and very few dogs are allergic to them. In fact, nearly all dogs can enjoy bananas especially performance or working dogs because they contain natural sugars which metabolize quickly providing instant energy.