The difference is in the taste. Dog food is not blended with the spices that humans are accustomed to, consequently it lacks palatability for humans.<p>One of the lessons I used to give to our kids was to eat some pieces of dog food and explain that while it doesn't taste wonderful, the import was that it was "FOOD" and could be used when there was no other alternative. Somehow, there is a common belief that dog food is bad for you and could harm you when that is not the case.<p>Then there is that old Joke:<p>Q: What's invisible and smells of Biff?<p>A: Old age pensioners' farts.