Using a dogâs ancestral diet as a model, the total amount of carbs consumed by a dogâs evolutionary predecessor is dramatically less than whatâs become the norm for todayâs kibbles. One sensible source estimates natural carbohydrate consumption for a dogâs ancestors at around 14 percent of total diet.he fact that a dog food doesnât need to contain any âcarbsâ at all seems hard to believe. But itâs true. You see, according to the National Research Council and compared to the other two major nutrients â protein and fat â no carbs are considered essential for a healthy canine diet. Dogs donât need corn.